Merge branch 'maint'

30 files changed, 2392 insertions, 912 deletions

diff --git a/lib/common_test/src/ct_config.erl b/lib/common_test/src/ct_config.erl
index a10d939919..a07e61199b 100644
--- a/lib/common_test/src/ct_config.erl
+++ b/lib/common_test/src/ct_config.erl
@@ -592,7 +592,7 @@ encrypt_config_file(SrcFileName, EncryptFileName, {file,KeyFile}) ->
 
 encrypt_config_file(SrcFileName, EncryptFileName, {key,Key}) ->
     _ = crypto:start(),
-    {Key,IVec} = make_crypto_key(Key),
+    {CryptoKey,IVec} = make_crypto_key(Key),
     case file:read_file(SrcFileName) of
 	{ok,Bin0} ->
 	    Bin1 = term_to_binary({SrcFileName,Bin0}),
@@ -600,7 +600,7 @@ encrypt_config_file(SrcFileName, EncryptFileName, {key,Key}) ->
 		       0 -> Bin1;
 		       N -> list_to_binary([Bin1,random_bytes(8-N)])
 		   end,
-	    EncBin = crypto:block_encrypt(des3_cbc, Key, IVec, Bin2),
+	    EncBin = crypto:block_encrypt(des3_cbc, CryptoKey, IVec, Bin2),
 	    case file:write_file(EncryptFileName, EncBin) of
 		ok ->
 		    io:format("~ts --(encrypt)--> ~ts~n",
@@ -631,10 +631,10 @@ decrypt_config_file(EncryptFileName, TargetFileName, {file,KeyFile}) ->
 
 decrypt_config_file(EncryptFileName, TargetFileName, {key,Key}) ->
     _ = crypto:start(),
-    {Key,IVec} = make_crypto_key(Key),
+    {CryptoKey,IVec} = make_crypto_key(Key),
     case file:read_file(EncryptFileName) of
 	{ok,Bin} ->
-	    DecBin = crypto:block_decrypt(des3_cbc, Key, IVec, Bin),
+	    DecBin = crypto:block_decrypt(des3_cbc, CryptoKey, IVec, Bin),
 	    case catch binary_to_term(DecBin) of
 		{'EXIT',_} ->
 		    {error,bad_file};
diff --git a/lib/kernel/doc/src/logger.xml b/lib/kernel/doc/src/logger.xml
index e09c5db5e3..0668676096 100644
--- a/lib/kernel/doc/src/logger.xml
+++ b/lib/kernel/doc/src/logger.xml
@@ -245,6 +245,12 @@ logger:error("error happened because: ~p", [Reason]). % Without macro
       </desc>
     </datatype>
     <datatype>
+      <name name="olp_config"/>
+      <desc>
+	<p></p>
+      </desc>
+    </datatype>
+    <datatype>
       <name name="primary_config"/>
       <desc>
 	<p>Primary configuration data for Logger. The following
@@ -597,8 +603,8 @@ start(_, []) ->
       <name name="get_config" arity="0" since="OTP 21.0"/>
       <fsummary>Look up the current Logger configuration</fsummary>
       <desc>
-        <p>Look up all current Logger configuration, including primary
-          and handler configuration, and module level settings.</p>
+        <p>Look up all current Logger configuration, including primary,
+          handler, and proxy configuration, and module level settings.</p>
       </desc>
     </func>
 
@@ -636,6 +642,17 @@ start(_, []) ->
     </func>
 
     <func>
+      <name name="get_proxy_config" arity="0" since="OTP 21.3"/>
+      <fsummary>Look up the current configuration for the Logger proxy.</fsummary>
+      <desc>
+        <p>Look up the current configuration for the Logger proxy.</p>
+	<p>For more information about the proxy, see
+	  section <seealso marker="logger_chapter#proxy">Logger
+	  Proxy</seealso> in the Kernel User's Guide.</p>
+      </desc>
+    </func>
+
+    <func>
       <name name="get_module_level" arity="0" since="OTP 21.0"/>
       <fsummary>Look up all current module levels.</fsummary>
       <desc>
@@ -801,6 +818,27 @@ start(_, []) ->
     </func>
 
     <func>
+      <name name="set_proxy_config" arity="1" since="OTP 21.3"/>
+      <fsummary>Set configuration data for the Logger proxy.</fsummary>
+      <desc>
+        <p>Set configuration data for the Logger proxy. This
+          overwrites the current proxy configuration. Keys that are not
+          specified in the <c><anno>Config</anno></c> map gets default
+          values.</p>
+	<p>To modify the existing configuration,
+	  use <seealso marker="#update_proxy_config-1">
+	    <c>update_proxy_config/1</c></seealso>, or, if a more
+	  complex merge is needed, read the current configuration
+	  with <seealso marker="#get_proxy_config-0"><c>get_proxy_config/0</c>
+	  </seealso>, then do the merge before writing the new
+	  configuration back with this function.</p>
+	<p>For more information about the proxy, see
+	  section <seealso marker="logger_chapter#proxy">Logger
+	  Proxy</seealso> in the Kernel User's Guide.</p>
+      </desc>
+    </func>
+
+    <func>
       <name name="set_module_level" arity="2" since="OTP 21.0"/>
       <fsummary>Set the log level for the specified modules.</fsummary>
       <desc>
@@ -1013,6 +1051,25 @@ logger:set_process_metadata(maps:merge(logger:get_process_metadata(), Meta)).
 	  </seealso>.</p>
       </desc>
     </func>
+
+    <func>
+      <name name="update_proxy_config" arity="1" since="OTP 21.3"/>
+      <fsummary>Update configuration data for the Logger proxy.</fsummary>
+      <desc>
+        <p>Update configuration data for the Logger proxy. This function
+          behaves as if it was implemented as follows:</p>
+	<code type="erl">
+Old = logger:get_proxy_config(),
+logger:set_proxy_config(maps:merge(Old, Config)).
+	</code>
+	<p>To overwrite the existing configuration without any merge,
+	  use <seealso marker="#set_proxy_config-1"><c>set_proxy_config/1</c>
+	  </seealso>.</p>
+	<p>For more information about the proxy, see
+	  section <seealso marker="logger_chapter#proxy">Logger
+	  Proxy</seealso> in the Kernel User's Guide.</p>
+      </desc>
+    </func>
   </funcs>
 
   <section>
diff --git a/lib/kernel/doc/src/logger_chapter.xml b/lib/kernel/doc/src/logger_chapter.xml
index c7e87e6668..03b9edcf8f 100644
--- a/lib/kernel/doc/src/logger_chapter.xml
+++ b/lib/kernel/doc/src/logger_chapter.xml
@@ -693,8 +693,10 @@ logger:debug(#{got => connection_request, id => Id, state => State},
 	  with <seealso marker="#logger_sasl_compatible">
 	    <c>logger_sasl_compatible</c></seealso>.</p>
 	<p>With this parameter, you can modify or disable the default
-	  handler, add custom handlers and primary logger filters, and
-	  set log levels per module.</p>
+	  handler, add custom handlers and primary logger filters, set
+	  log levels per module, and modify
+	  the <seealso marker="#proxy">proxy</seealso>
+	  configuration.</p>
 	<p><c>Config</c> is any (zero or more) of the following:</p>
 	<taglist>
           <tag><c>{handler, default, undefined}</c></tag>
@@ -746,6 +748,14 @@ logger:debug(#{got => connection_request, id => Id, state => State},
 	    <p>for each <c>Module</c>.</p>
 	    <p>Multiple entries of this type are allowed.</p>
 	  </item>
+	  <tag><c>{proxy, ProxyConfig}</c></tag>
+	  <item>
+	    <p>Sets the proxy configuration, equivalent to calling</p>
+	    <pre><seealso marker="logger#set_proxy_config/1">
+		logger:set_proxy_config(ProxyConfig)
+	    </seealso></pre>
+	    <p>Only one entry of this type is allowed.</p>
+	  </item>
 	</taglist>
 	<p>See
 	  section <seealso marker="#config_examples">Configuration
@@ -1334,9 +1344,50 @@ logger:add_handler(my_disk_log_h, logger_disk_log_h,
   </section>
 
   <section>
+    <marker id="proxy"/>
+    <title>Logger Proxy</title>
+    <p>The Logger proxy is an Erlang process which is part of the
+      Kernel application's supervision tree. During startup, the proxy
+      process registers itself as the <c>system_logger</c>, meaning
+      that log events produced by the emulator are sent to this
+      process.</p>
+    <p>When a log event is issued on a process which has its group
+      leader on a remote node, Logger automatically forwards the log
+      event to the group leader's node. To achieve this, it first
+      sends the log event as an Erlang message from the original
+      client process to the proxy on the local node, and the proxy in
+      turn forwards the event to the proxy on the remote node.</p>
+    <p>When receiving a log event, either from the emulator or from a
+      remote node, the proxy calls the Logger API to log the event.</p>
+    <p>The proxy process is overload protected in the same way as
+      described in
+      section <seealso marker="#overload_protection">Protecting the
+      Handler from Overload</seealso>, but with the following default
+      values:</p>
+    <code>
+    #{sync_mode_qlen => 500,
+      drop_mode_qlen => 1000,
+      flush_qlen => 5000,
+      burst_limit_enable => false,
+      overload_kill_enable => false}</code>
+    <p>For log events from the emulator, synchronous message passing
+      mode is not applicable, since all messages are passed
+      asynchronously by the emulator. Drop mode is achieved by setting
+      the <c>system_logger</c> to <c>undefined</c>, forcing the
+      emulator to drop events until it is set back to the proxy pid
+      again.</p>
+    <p>The proxy uses <seealso marker="erts:erlang#send_nosuspend/2">
+	<c>erlang:send_nosuspend/2</c></seealso> when sending log
+      events to a remote node. If the message could not be sent
+      without suspending the sender, it is dropped. This is to avoid
+      blocking the proxy process.</p>
+  </section>
+
+  <section>
     <title>See Also</title>
     <p>
       <seealso marker="disk_log"><c>disk_log(3)</c></seealso>,
+      <seealso marker="erts:erlang"><c>erlang(3)</c></seealso>,
       <seealso marker="error_logger"><c>error_logger(3)</c></seealso>,
       <seealso marker="logger"><c>logger(3)</c></seealso>,
       <seealso marker="logger_disk_log_h"><c>logger_disk_log_h(3)</c></seealso>,
diff --git a/lib/kernel/src/Makefile b/lib/kernel/src/Makefile
index 57f17defc8..3d1506ea08 100644
--- a/lib/kernel/src/Makefile
+++ b/lib/kernel/src/Makefile
@@ -118,6 +118,8 @@ MODULES = \
 	logger_h_common \
 	logger_filters \
         logger_formatter \
+	logger_olp \
+	logger_proxy \
         logger_server \
         logger_simple_h \
         logger_sup \
@@ -151,7 +153,7 @@ INTERNAL_HRL_FILES= application_master.hrl disk_log.hrl \
         inet_dns.hrl inet_res.hrl \
         inet_boot.hrl inet_config.hrl inet_int.hrl \
 	inet_dns_record_adts.hrl \
-	logger_internal.hrl logger_h_common.hrl
+	logger_internal.hrl logger_olp.hrl logger_h_common.hrl
 
 ERL_FILES= $(MODULES:%=%.erl)
 
@@ -279,6 +281,8 @@ $(EBIN)/logger_config.beam: logger_internal.hrl ../include/logger.hrl
 $(EBIN)/logger_disk_log_h.beam: logger_h_common.hrl logger_internal.hrl ../include/logger.hrl ../include/file.hrl
 $(EBIN)/logger_filters.beam: logger_internal.hrl ../include/logger.hrl
 $(EBIN)/logger_formatter.beam: logger_internal.hrl ../include/logger.hrl
+$(EBIN)/logger_olp.beam: logger_olp.hrl logger_internal.hrl
+$(EBIN)/logger_proxy.beam: logger_internal.hrl
 $(EBIN)/logger_server.beam: logger_internal.hrl ../include/logger.hrl
 $(EBIN)/logger_simple_h.beam: logger_internal.hrl ../include/logger.hrl
 $(EBIN)/logger_std_h.beam: logger_h_common.hrl logger_internal.hrl ../include/logger.hrl ../include/file.hrl
diff --git a/lib/kernel/src/kernel.app.src b/lib/kernel/src/kernel.app.src
index fe073621c8..a1d9e8e215 100644
--- a/lib/kernel/src/kernel.app.src
+++ b/lib/kernel/src/kernel.app.src
@@ -68,6 +68,8 @@
              logger_formatter,
              logger_h_common,
              logger_handler_watcher,
+             logger_olp,
+             logger_proxy,
              logger_server,
              logger_simple_h,
              logger_std_h,
diff --git a/lib/kernel/src/logger.erl b/lib/kernel/src/logger.erl
index 6762998d4f..abdd9a9ceb 100644
--- a/lib/kernel/src/logger.erl
+++ b/lib/kernel/src/logger.erl
@@ -43,11 +43,14 @@
          get_module_level/0, get_module_level/1,
          set_primary_config/1, set_primary_config/2,
          set_handler_config/2, set_handler_config/3,
+         set_proxy_config/1,
          update_primary_config/1,
          update_handler_config/2, update_handler_config/3,
+         update_proxy_config/1,
          update_formatter_config/2, update_formatter_config/3,
          get_primary_config/0, get_handler_config/1,
          get_handler_config/0, get_handler_ids/0, get_config/0,
+         get_proxy_config/0,
          add_handlers/1]).
 
 %% Private configuration
@@ -122,6 +125,18 @@
                           {filters,log | stop,[{filter_id(),filter()}]} |
                           {module_level,level(),[module()]}].
 
+-type olp_config() :: #{sync_mode_qlen => non_neg_integer(),
+                        drop_mode_qlen => pos_integer(),
+                        flush_qlen => pos_integer(),
+                        burst_limit_enable => boolean(),
+                        burst_limit_max_count => pos_integer(),
+                        burst_limit_window_time => pos_integer(),
+                        overload_kill_enable => boolean(),
+                        overload_kill_qlen => pos_integer(),
+                        overload_kill_mem_size => pos_integer(),
+                        overload_kill_restart_after =>
+                            non_neg_integer() | infinity}.
+
 -export_type([log_event/0,
               level/0,
               report/0,
@@ -137,7 +152,8 @@
               filter_arg/0,
               filter_return/0,
               config_handler/0,
-              formatter_config/0]).
+              formatter_config/0,
+              olp_config/0]).
 
 %%%-----------------------------------------------------------------
 %%% API
@@ -390,6 +406,7 @@ set_primary_config(Key,Value) ->
 set_primary_config(Config) ->
     logger_server:set_config(primary,Config).
 
+
 -spec set_handler_config(HandlerId,level,Level) -> Return when
       HandlerId :: handler_id(),
       Level :: level() | all | none,
@@ -419,6 +436,11 @@ set_handler_config(HandlerId,Key,Value) ->
 set_handler_config(HandlerId,Config) ->
     logger_server:set_config(HandlerId,Config).
 
+-spec set_proxy_config(Config) -> ok | {error,term()} when
+      Config :: olp_config().
+set_proxy_config(Config) ->
+    logger_server:set_config(proxy,Config).
+
 -spec update_primary_config(Config) -> ok | {error,term()} when
       Config :: primary_config().
 update_primary_config(Config) ->
@@ -453,6 +475,11 @@ update_handler_config(HandlerId,Key,Value) ->
 update_handler_config(HandlerId,Config) ->
     logger_server:update_config(HandlerId,Config).
 
+-spec update_proxy_config(Config) -> ok | {error,term()} when
+      Config :: olp_config().
+update_proxy_config(Config) ->
+    logger_server:update_config(proxy,Config).
+
 -spec get_primary_config() -> Config when
       Config :: primary_config().
 get_primary_config() ->
@@ -486,6 +513,12 @@ get_handler_ids() ->
     {ok,#{handlers:=HandlerIds}} = logger_config:get(?LOGGER_TABLE,primary),
     HandlerIds.
 
+-spec get_proxy_config() -> Config when
+      Config :: olp_config().
+get_proxy_config() ->
+    {ok,Config} = logger_config:get(?LOGGER_TABLE,proxy),
+    Config.
+
 -spec update_formatter_config(HandlerId,FormatterConfig) ->
                                      ok | {error,term()} when
       HandlerId :: handler_id(),
@@ -606,10 +639,12 @@ unset_process_metadata() ->
 
 -spec get_config() -> #{primary=>primary_config(),
                         handlers=>[handler_config()],
+                        proxy=>olp_config(),
                         module_levels=>[{module(),level() | all | none}]}.
 get_config() ->
     #{primary=>get_primary_config(),
       handlers=>get_handler_config(),
+      proxy=>get_proxy_config(),
       module_levels=>lists:keysort(1,get_module_level())}.
 
 -spec internal_init_logger() -> ok | {error,term()}.
@@ -672,6 +707,17 @@ init_kernel_handlers(Env) ->
 %% This function is responsible for resolving the handler config
 %% and then starting the correct handlers. This is done after the
 %% kernel supervisor tree has been started as it needs the logger_sup.
+add_handlers(kernel) ->
+    Env = get_logger_env(kernel),
+    case get_proxy_opts(Env) of
+        undefined ->
+            add_handlers(kernel,Env);
+        Opts ->
+            case set_proxy_config(Opts) of
+                ok -> add_handlers(kernel,Env);
+                {error, Reason} -> {error,{bad_proxy_config,Reason}}
+            end
+    end;
 add_handlers(App) when is_atom(App) ->
     add_handlers(App,get_logger_env(App));
 add_handlers(HandlerConfig) ->
@@ -729,6 +775,8 @@ check_logger_config(kernel,[{filters,_,_}|Env]) ->
     check_logger_config(kernel,Env);
 check_logger_config(kernel,[{module_level,_,_}|Env]) ->
     check_logger_config(kernel,Env);
+check_logger_config(kernel,[{proxy,_}|Env]) ->
+    check_logger_config(kernel,Env);
 check_logger_config(_,Bad) ->
     throw(Bad).
 
@@ -784,6 +832,13 @@ get_primary_filters(Env) ->
         _ -> throw({multiple_filters,Env})
     end.
 
+get_proxy_opts(Env) ->
+    case [P || P={proxy,_} <- Env] of
+        [{proxy,Opts}] -> Opts;
+        [] -> undefined;
+        _ -> throw({multiple_proxies,Env})
+    end.
+
 %% This function looks at the kernel logger environment
 %% and updates it so that the correct logger is configured
 init_default_config(Type,Env) when Type==standard_io;
@@ -880,30 +935,30 @@ log_allowed(Location,Level,Msg,Meta0) when is_map(Meta0) ->
              maps:merge(Location,maps:merge(proc_meta(),Meta0))),
     case node(maps:get(gl,Meta)) of
         Node when Node=/=node() ->
-            log_remote(Node,Level,Msg,Meta),
-            do_log_allowed(Level,Msg,Meta);
+            log_remote(Node,Level,Msg,Meta);
         _ ->
-            do_log_allowed(Level,Msg,Meta)
-    end.
+            ok
+    end,
+    do_log_allowed(Level,Msg,Meta,tid()).
 
-do_log_allowed(Level,{Format,Args}=Msg,Meta)
+do_log_allowed(Level,{Format,Args}=Msg,Meta,Tid)
   when ?IS_LEVEL(Level),
        is_list(Format),
        is_list(Args),
        is_map(Meta) ->
-    logger_backend:log_allowed(#{level=>Level,msg=>Msg,meta=>Meta},tid());
-do_log_allowed(Level,Report,Meta)
+    logger_backend:log_allowed(#{level=>Level,msg=>Msg,meta=>Meta},Tid);
+do_log_allowed(Level,Report,Meta,Tid)
   when ?IS_LEVEL(Level),
        ?IS_REPORT(Report),
        is_map(Meta) ->
     logger_backend:log_allowed(#{level=>Level,msg=>{report,Report},meta=>Meta},
-                               tid());
-do_log_allowed(Level,String,Meta)
+                               Tid);
+do_log_allowed(Level,String,Meta,Tid)
   when ?IS_LEVEL(Level),
        ?IS_STRING(String),
        is_map(Meta) ->
     logger_backend:log_allowed(#{level=>Level,msg=>{string,String},meta=>Meta},
-                               tid()).
+                               Tid).
 tid() ->
     ets:whereis(?LOGGER_TABLE).
 
@@ -913,7 +968,7 @@ log_remote(Node,Level,Msg,Meta) ->
     log_remote(Node,{log,Level,Msg,Meta}).
 
 log_remote(Node,Request) ->
-    {logger,Node} ! Request,
+    logger_proxy:log({remote,Node,Request}),
     ok.
 
 add_default_metadata(Meta) ->
diff --git a/lib/kernel/src/logger_config.erl b/lib/kernel/src/logger_config.erl
index 5e9faf332c..5024d20cfe 100644
--- a/lib/kernel/src/logger_config.erl
+++ b/lib/kernel/src/logger_config.erl
@@ -66,6 +66,8 @@ get(Tid,What) ->
     case ets:lookup(Tid,table_key(What)) of
         [{_,_,Config}] ->
             {ok,Config};
+        [{_,Config}] when What=:=proxy ->
+            {ok,Config};
         [] ->
             {error,{not_found,What}}
     end.
@@ -79,10 +81,15 @@ get(Tid,What,Level) ->
         [Data] -> {ok,Data}
     end.
 
+create(Tid,proxy,Config) ->
+    ets:insert(Tid,{table_key(proxy),Config});
 create(Tid,What,Config) ->
     LevelInt = level_to_int(maps:get(level,Config)),
     ets:insert(Tid,{table_key(What),LevelInt,Config}).
 
+set(Tid,proxy,Config) ->
+    ets:insert(Tid,{table_key(proxy),Config}),
+    ok;
 set(Tid,What,Config) ->
     LevelInt = level_to_int(maps:get(level,Config)),
     %% Should do this only if the level has actually changed. Possibly
@@ -148,5 +155,6 @@ int_to_level(?LOG_ALL) -> all.
 %%%-----------------------------------------------------------------
 %%% Internal
 
+table_key(proxy) -> ?PROXY_KEY;
 table_key(primary) -> ?PRIMARY_KEY;
 table_key(HandlerId) -> {?HANDLER_KEY,HandlerId}.
diff --git a/lib/kernel/src/logger_disk_log_h.erl b/lib/kernel/src/logger_disk_log_h.erl
index 41e0d51a9d..47b39da900 100644
--- a/lib/kernel/src/logger_disk_log_h.erl
+++ b/lib/kernel/src/logger_disk_log_h.erl
@@ -24,7 +24,7 @@
 -include("logger_h_common.hrl").
 
 %%% API
--export([info/1, filesync/1, reset/1]).
+-export([filesync/1]).
 
 %% logger_h_common callbacks
 -export([init/2, check_config/4, reset_state/2,
@@ -47,25 +47,6 @@
 filesync(Name) ->
     logger_h_common:filesync(?MODULE,Name).
 
-%%%-----------------------------------------------------------------
-%%%
--spec info(Name) -> Info | {error,Reason} when
-      Name :: atom(),
-      Info :: term(),
-      Reason :: handler_busy | {badarg,term()}.
-
-info(Name) ->
-    logger_h_common:info(?MODULE,Name).
-
-%%%-----------------------------------------------------------------
-%%%
--spec reset(Name) -> ok | {error,Reason} when
-      Name :: atom(),
-      Reason :: handler_busy | {badarg,term()}.
-
-reset(Name) ->
-    logger_h_common:reset(?MODULE,Name).
-
 %%%===================================================================
 %%% logger callbacks
 %%%===================================================================
diff --git a/lib/kernel/src/logger_h_common.erl b/lib/kernel/src/logger_h_common.erl
index 74a2d158fc..e69f6de38d 100644
--- a/lib/kernel/src/logger_h_common.erl
+++ b/lib/kernel/src/logger_h_common.erl
@@ -24,11 +24,11 @@
 -include("logger_internal.hrl").
 
 %% API
--export([start_link/1, info/2, filesync/2, reset/2]).
+-export([filesync/2]).
 
-%% gen_server and proc_lib callbacks
--export([init/1, handle_call/3, handle_cast/2, handle_info/2,
-         terminate/2, code_change/3]).
+%% logger_olp callbacks
+-export([init/1, handle_load/2, handle_call/3, handle_cast/2, handle_info/2,
+         terminate/2, code_change/3, notify/2, reset_state/1]).
 
 %% logger callbacks
 -export([log/2, adding_handler/1, removing_handler/1, changing_config/3,
@@ -37,52 +37,45 @@
 %% Library functions for handlers
 -export([error_notify/1]).
 
-%%%-----------------------------------------------------------------
--define(CONFIG_KEYS,[sync_mode_qlen,
-                     drop_mode_qlen,
-                     flush_qlen,
-                     burst_limit_enable,
-                     burst_limit_max_count,
-                     burst_limit_window_time,
-                     overload_kill_enable,
-                     overload_kill_qlen,
-                     overload_kill_mem_size,
-                     overload_kill_restart_after,
-                     filesync_repeat_interval]).
--define(READ_ONLY_KEYS,[handler_pid,mode_tab]).
+-define(OLP_KEYS,[sync_mode_qlen,
+                  drop_mode_qlen,
+                  flush_qlen,
+                  burst_limit_enable,
+                  burst_limit_max_count,
+                  burst_limit_window_time,
+                  overload_kill_enable,
+                  overload_kill_qlen,
+                  overload_kill_mem_size,
+                  overload_kill_restart_after]).
+
+-define(COMMON_KEYS,[filesync_repeat_interval]).
+
+-define(READ_ONLY_KEYS,[olp]).
 
 %%%-----------------------------------------------------------------
 %%% API
 
 %% This function is called by the logger_sup supervisor
-start_link(Args) ->
-    proc_lib:start_link(?MODULE,init,[Args]).
-
 filesync(Module, Name) ->
     call(Module, Name, filesync).
 
-info(Module, Name) ->
-    call(Module, Name, info).
-
-reset(Module, Name) ->
-    call(Module, Name, reset).
-
 %%%-----------------------------------------------------------------
 %%% Handler being added
 adding_handler(#{id:=Name,module:=Module}=Config) ->
     HConfig0 = maps:get(config, Config, #{}),
-    HandlerConfig0 = maps:without(?CONFIG_KEYS,HConfig0),
+    HandlerConfig0 = maps:without(?OLP_KEYS++?COMMON_KEYS,HConfig0),
     case Module:check_config(Name,set,undefined,HandlerConfig0) of
         {ok,HandlerConfig} ->
-            ModifiedCommon = maps:with(?CONFIG_KEYS,HandlerConfig),
-            CommonConfig0 = maps:with(?CONFIG_KEYS,HConfig0),
+            ModifiedCommon = maps:with(?COMMON_KEYS,HandlerConfig),
+            CommonConfig0 = maps:with(?COMMON_KEYS,HConfig0),
             CommonConfig = maps:merge(
                              maps:merge(get_default_config(), CommonConfig0),
                              ModifiedCommon),
             case check_config(CommonConfig) of
                 ok ->
                     HConfig = maps:merge(CommonConfig,HandlerConfig),
-                    start(Config#{config => HConfig});
+                    OlpOpts = maps:with(?OLP_KEYS,HConfig0),
+                    start(OlpOpts, Config#{config => HConfig});
                 {error,Faulty} ->
                     {error,{invalid_config,Module,Faulty}}
             end;
@@ -92,11 +85,11 @@ adding_handler(#{id:=Name,module:=Module}=Config) ->
 
 %%%-----------------------------------------------------------------
 %%% Handler being removed
-removing_handler(#{id:=Name, module:=Module}) ->
+removing_handler(#{id:=Name, module:=Module, config:=#{olp:=Olp}}) ->
     case whereis(?name_to_reg_name(Module,Name)) of
         undefined ->
             ok;
-        Pid ->
+        _Pid ->
             %% We don't want to do supervisor:terminate_child here
             %% since we need to distinguish this explicit stop from a
             %% system termination in order to avoid circular attempts
@@ -106,7 +99,7 @@ removing_handler(#{id:=Name, module:=Module}) ->
             %% the restart type is temporary, which means that the
             %% child specification is automatically removed from the
             %% supervisor when the process dies.
-            _ = gen_server:call(Pid, stop),
+            _ = logger_olp:stop(Olp),
             ok
     end.
 
@@ -116,34 +109,52 @@ changing_config(SetOrUpdate,
                 #{id:=Name,config:=OldHConfig,module:=Module},
                 NewConfig0) ->
     NewHConfig0 = maps:get(config, NewConfig0, #{}),
-    OldHandlerConfig = maps:without(?CONFIG_KEYS++?READ_ONLY_KEYS,OldHConfig),
-    NewHandlerConfig0 = maps:without(?CONFIG_KEYS++?READ_ONLY_KEYS,NewHConfig0),
+    NoHandlerKeys = ?OLP_KEYS++?COMMON_KEYS++?READ_ONLY_KEYS,
+    OldHandlerConfig = maps:without(NoHandlerKeys,OldHConfig),
+    NewHandlerConfig0 = maps:without(NoHandlerKeys,NewHConfig0),
     case Module:check_config(Name, SetOrUpdate,
                              OldHandlerConfig,NewHandlerConfig0) of
         {ok, NewHandlerConfig} ->
-            ModifiedCommon = maps:with(?CONFIG_KEYS,NewHandlerConfig),
-            NewCommonConfig0 = maps:with(?CONFIG_KEYS,NewHConfig0),
+            ModifiedCommon = maps:with(?COMMON_KEYS,NewHandlerConfig),
+            NewCommonConfig0 = maps:with(?COMMON_KEYS,NewHConfig0),
+            OldCommonConfig = maps:with(?COMMON_KEYS,OldHConfig),
             CommonDefault =
                 case SetOrUpdate of
                     set ->
                         get_default_config();
                     update ->
-                        maps:with(?CONFIG_KEYS,OldHConfig)
+                        OldCommonConfig
                 end,
             NewCommonConfig = maps:merge(
                                 maps:merge(CommonDefault,NewCommonConfig0),
                                 ModifiedCommon),
             case check_config(NewCommonConfig) of
                 ok ->
-                    ReadOnly = maps:with(?READ_ONLY_KEYS,OldHConfig),
-                    NewHConfig = maps:merge(
-                                   maps:merge(NewCommonConfig,NewHandlerConfig),
-                                   ReadOnly),
-                    NewConfig = NewConfig0#{config=>NewHConfig},
-                    HPid = maps:get(handler_pid,OldHConfig),
-                    case call(HPid, {change_config,NewConfig}) of
-                        ok      -> {ok,NewConfig};
-                        Error  -> Error
+                    OlpDefault =
+                        case SetOrUpdate of
+                            set ->
+                                logger_olp:get_default_opts();
+                            update ->
+                                maps:with(?OLP_KEYS,OldHConfig)
+                        end,
+                    Olp = maps:get(olp,OldHConfig),
+                    NewOlpOpts = maps:merge(OlpDefault,
+                                            maps:with(?OLP_KEYS,NewHConfig0)),
+                    case logger_olp:set_opts(Olp,NewOlpOpts) of
+                        ok ->
+                            maybe_set_repeated_filesync(Olp,OldCommonConfig,
+                                                        NewCommonConfig),
+                            ReadOnly = maps:with(?READ_ONLY_KEYS,OldHConfig),
+                            NewHConfig =
+                                maps:merge(
+                                  maps:merge(
+                                    maps:merge(NewCommonConfig,NewHandlerConfig),
+                                    ReadOnly),
+                                  NewOlpOpts),
+                            NewConfig = NewConfig0#{config=>NewHConfig},
+                            {ok,NewConfig};
+                        Error  ->
+                            Error
                     end;
                 {error,Faulty} ->
                     {error,{invalid_config,Module,Faulty}}
@@ -158,14 +169,12 @@ changing_config(SetOrUpdate,
       LogEvent :: logger:log_event(),
       Config :: logger:handler_config().
 
-log(LogEvent, Config = #{id := Name,
-                         config := #{handler_pid := HPid,
-                                     mode_tab := ModeTab}}) ->
+log(LogEvent, Config = #{config := #{olp:=Olp}}) ->
     %% if the handler has crashed, we must drop this event
     %% and hope the handler restarts so we can try again
-    true = is_process_alive(HPid),
+    true = is_process_alive(logger_olp:get_pid(Olp)),
     Bin = log_to_binary(LogEvent, Config),
-    call_cast_or_drop(Name, HPid, ModeTab, Bin).
+    logger_olp:load(Olp,Bin).
 
 %%%-----------------------------------------------------------------
 %%% Remove internal fields from configuration
@@ -180,18 +189,23 @@ filter_config(#{config:=HConfig}=Config) ->
 %%%
 %%% The handler process is linked to logger_sup, which is part of the
 %%% kernel application's supervision tree.
-start(#{id := Name} = Config0) ->
+start(OlpOpts0, #{id := Name, module:=Module, config:=HConfig} = Config0) ->
+    RegName = ?name_to_reg_name(Module,Name),
     ChildSpec =
         #{id       => Name,
-          start    => {?MODULE, start_link, [Config0]},
+          start    => {logger_olp, start_link, [RegName,?MODULE,
+                                                Config0, OlpOpts0]},
           restart  => temporary,
           shutdown => 2000,
           type     => worker,
           modules  => [?MODULE]},
     case supervisor:start_child(logger_sup, ChildSpec) of
-        {ok,Pid,Config} ->
+        {ok,Pid,Olp} ->
             ok = logger_handler_watcher:register_handler(Name,Pid),
-            {ok,Config};
+            OlpOpts = logger_olp:get_opts(Olp),
+            {ok,Config0#{config=>(maps:merge(HConfig,OlpOpts))#{olp=>Olp}}};
+        {error,{Reason,Ch}} when is_tuple(Ch), element(1,Ch)==child ->
+            {error,Reason};
         Error ->
             Error
     end.
@@ -200,103 +214,50 @@ start(#{id := Name} = Config0) ->
 %%% gen_server callbacks
 %%%===================================================================
 
-init(#{id := Name, module := Module,
-       formatter := Formatter, config := HConfig0} = Config0) ->
-    RegName = ?name_to_reg_name(Module,Name),
-    register(RegName, self()),
+init(#{id := Name, module := Module, config := HConfig}) ->
     process_flag(trap_exit, true),
-    process_flag(message_queue_data, off_heap),
 
     ?init_test_hooks(),
-    ?start_observation(Name),
 
-    case Module:init(Name, HConfig0) of
+    case Module:init(Name, HConfig) of
         {ok,HState} ->
-            try ets:new(Name, [public]) of
-                ModeTab ->
-                    ?set_mode(ModeTab, async),
-                    T0 = ?timestamp(),
-                    HConfig = HConfig0#{handler_pid => self(),
-                                        mode_tab => ModeTab},
-                    Config = Config0#{config => HConfig},
-                    proc_lib:init_ack({ok,self(),Config}),
-                    %% Storing common config in state to avoid copying
-                    %% (sending) the config data for each log message
-                    CommonConfig = maps:with(?CONFIG_KEYS,HConfig),
-                    State =
-                        ?merge_with_stats(
-                           CommonConfig#{id => Name,
-                                         module => Module,
-                                         mode_tab => ModeTab,
-                                         mode => async,
-                                         ctrl_sync_count =>
-                                             ?CONTROLLER_SYNC_INTERVAL,
-                                         last_qlen => 0,
-                                         last_log_ts => T0,
-                                         last_op => sync,
-                                         burst_win_ts => T0,
-                                         burst_msg_count => 0,
-                                         formatter => Formatter,
-                                         handler_state => HState}),
-                    State1 = set_repeated_filesync(State),
-                    unset_restart_flag(State1),
-                    gen_server:enter_loop(?MODULE, [], State1)
-            catch
-                _:Error ->
-                    unregister(RegName),
-                    error_notify({init_handler,Name,Error}),
-                    proc_lib:init_ack(Error)
-            end;
+            %% Storing common config in state to avoid copying
+            %% (sending) the config data for each log message
+            CommonConfig = maps:with(?COMMON_KEYS,HConfig),
+            State = CommonConfig#{id => Name,
+                                  module => Module,
+                                  ctrl_sync_count =>
+                                      ?CONTROLLER_SYNC_INTERVAL,
+                                  last_op => sync,
+                                  handler_state => HState},
+            State1 = set_repeated_filesync(State),
+            {ok,State1};
         Error ->
-            unregister(RegName),
-            error_notify({init_handler,Name,Error}),
-            proc_lib:init_ack(Error)
+            Error
     end.
 
-%% This is the synchronous log event.
-handle_call({log, Bin}, _From, State) ->
-    {Result,State1} = do_log(Bin, call, State),
-    %% Result == ok | dropped
-    {reply,Result, State1};
+%% This is the log event.
+handle_load(Bin, #{id:=Name,
+                   module:=Module,
+                   handler_state:=HandlerState,
+                   ctrl_sync_count := CtrlSync}=State) ->
+    if CtrlSync==0 ->
+            {_,HS1} = Module:write(Name, sync, Bin, HandlerState),
+            State#{handler_state => HS1,
+                   ctrl_sync_count => ?CONTROLLER_SYNC_INTERVAL,
+                   last_op=>write};
+       true ->
+            {_,HS1} = Module:write(Name, async, Bin, HandlerState),
+            State#{handler_state => HS1,
+                   ctrl_sync_count => CtrlSync-1,
+                   last_op=>write}
+    end.
 
 handle_call(filesync, _From, State = #{id := Name,
                                        module := Module,
                                        handler_state := HandlerState}) ->
     {Result,HandlerState1} = Module:filesync(Name,sync,HandlerState),
-    {reply, Result, State#{handler_state=>HandlerState1, last_op=>sync}};
-
-handle_call({change_config, #{formatter:=Formatter, config:=NewHConfig}}, _From,
-            State = #{filesync_repeat_interval := FSyncInt0}) ->
-    %% In the future, if handler_state must be updated due to config
-    %% change, then we need to add a callback to Module here.
-    CommonConfig = maps:with(?CONFIG_KEYS,NewHConfig),
-    State1 = maps:merge(State, CommonConfig),
-    State2 =
-        case maps:get(filesync_repeat_interval, NewHConfig) of
-            FSyncInt0 ->
-                State1;
-            _FSyncInt1 ->
-                set_repeated_filesync(cancel_repeated_filesync(State1))
-        end,
-    {reply, ok, State2#{formatter:=Formatter}};
-
-handle_call(info, _From, State) ->
-    {reply, State, State};
-
-handle_call(reset, _From,
-            #{id:=Name,module:=Module,handler_state:=HandlerState}=State) ->
-    State1 = ?merge_with_stats(State),
-    {reply, ok, State1#{last_qlen => 0,
-                        last_log_ts => ?timestamp(),
-                        handler_state => Module:reset_state(Name,HandlerState)}};
-
-handle_call(stop, _From, State) ->
-    {stop, {shutdown,stopped}, ok, State}.
-
-%% This is the asynchronous log event.
-handle_cast({log, Bin}, State) ->
-    {_,State1} = do_log(Bin, cast, State),
-    {noreply, State1};
+    {reply, Result, State#{handler_state=>HandlerState1, last_op=>sync}}.
 
 %% If FILESYNC_REPEAT_INTERVAL is set to a millisec value, this
 %% clause gets called repeatedly by the handler. In order to
@@ -319,168 +280,83 @@ handle_cast(repeated_filesync,
                 {_,HS} = Module:filesync(Name, async, HandlerState),
                 State#{handler_state => HS, last_op => sync}
         end,
-    {noreply,set_repeated_filesync(State1)}.
+    {noreply,set_repeated_filesync(State1)};
+
+handle_cast({set_repeated_filesync,FSyncInt},State) ->
+    State1 = State#{filesync_repeat_interval=>FSyncInt},
+    State2 = set_repeated_filesync(cancel_repeated_filesync(State1)),
+    {noreply, State2}.
 
 handle_info(Info, #{id := Name, module := Module,
                     handler_state := HandlerState} = State) ->
     {noreply,State#{handler_state => Module:handle_info(Name,Info,HandlerState)}}.
 
-terminate(Reason, State = #{id := Name,
-                            module := Module,
-                            handler_state := HandlerState}) ->
+terminate(overloaded=Reason, #{id:=Name}=State) ->
+    _ = log_handler_info(Name,"Handler ~p overloaded and stopping",[Name],State),
+    do_terminate(Reason,State),
+    ConfigResult = logger:get_handler_config(Name),
+    case ConfigResult of
+        {ok,#{module:=Module}=HConfig0} ->
+            spawn(fun() -> logger:remove_handler(Name) end),
+            HConfig = try Module:filter_config(HConfig0)
+                      catch _:_ -> HConfig0
+                      end,
+            {ok,fun() -> logger:add_handler(Name,Module,HConfig) end};
+        Error ->
+            error_notify({Name,restart_impossible,Error}),
+            Error
+    end;
+terminate(Reason, State) ->
+    do_terminate(Reason, State).
+
+do_terminate(Reason, State = #{id := Name,
+                               module := Module,
+                               handler_state := HandlerState}) ->
     _ = cancel_repeated_filesync(State),
     _ = Module:terminate(Name, Reason, HandlerState),
-    ok = stop_or_restart(Name, Reason, State),
-    unregister(?name_to_reg_name(Module, Name)),
     ok.
 
 code_change(_OldVsn, State, _Extra) ->
     {ok, State}.
 
+reset_state(#{id:=Name, module:=Module, handler_state:=HandlerState} = State) ->
+    State#{handler_state=>Module:reset_state(Name, HandlerState)}.
 
 %%%-----------------------------------------------------------------
 %%% Internal functions
 call(Module, Name, Op) when is_atom(Name) ->
-    call(?name_to_reg_name(Module,Name), Op);
+    case logger_olp:call(?name_to_reg_name(Module,Name), Op) of
+        {error,busy} -> {error,handler_busy};
+        Other -> Other
+    end;
 call(_, Name, Op) ->
     {error,{badarg,{Op,[Name]}}}.
 
-call(Server, Msg) ->
-    try
-        gen_server:call(Server, Msg, ?DEFAULT_CALL_TIMEOUT)
-    catch
-        _:{timeout,_} -> {error,handler_busy}
-    end.
-
-%% check for overload between every event (and set Mode to async,
-%% sync or drop accordingly), but never flush the whole mailbox
-%% before LogWindowSize events have been handled
-do_log(Bin, CallOrCast, State = #{id:=Name, mode:=Mode0}) ->
-    T1 = ?timestamp(),
-
-    %% check if the handler is getting overloaded, or if it's
-    %% recovering from overload (the check must be done for each
-    %% event to react quickly to large bursts of events and
-    %% to ensure that the handler can never end up in drop mode
-    %% with an empty mailbox, which would stop operation)
-    {Mode1,QLen,Mem,State1} = check_load(State),
-
-    if (Mode1 == drop) andalso (Mode0 =/= drop) ->
-            log_handler_info(Name, "Handler ~p switched to drop mode",
-                             [Name], State);
-       (Mode0 == drop) andalso ((Mode1 == async) orelse (Mode1 == sync)) ->
-            log_handler_info(Name, "Handler ~p switched to ~w mode",
-                             [Name,Mode1], State);
-       true ->
-            ok
-    end,
-
-    %% kill the handler if it can't keep up with the load
-    kill_if_choked(Name, QLen, Mem, State),
-
-    if Mode1 == flush ->
-            flush(Name, QLen, T1, State1);
-       true ->
-            write(Name, Mode1, T1, Bin, CallOrCast, State1)
-    end.
-
-%% this clause is called by do_log/3 after an overload check
-%% has been performed, where QLen > FlushQLen
-flush(Name, _QLen0, T1, State=#{last_log_ts := _T0, mode_tab := ModeTab}) ->
-    %% flush messages in the mailbox (a limited number in
-    %% order to not cause long delays)
-    NewFlushed = flush_log_events(?FLUSH_MAX_N),
-
-    %% write info in log about flushed messages
+notify({mode_change,Mode0,Mode1},#{id:=Name}=State) ->
+    log_handler_info(Name,"Handler ~p switched from  ~p to ~p mode",
+                     [Name,Mode0,Mode1], State);
+notify({flushed,Flushed},#{id:=Name}=State) ->
     log_handler_info(Name, "Handler ~p flushed ~w log events",
-                     [Name,NewFlushed], State),
-
-    %% because of the receive loop when flushing messages, the
-    %% handler will be scheduled out often and the mailbox could
-    %% grow very large, so we'd better check the queue again here
-    {_,_QLen1} = process_info(self(), message_queue_len),
-    ?observe(Name,{max_qlen,_QLen1}),
-
-    %% Add 1 for the current log event
-    ?observe(Name,{flushed,NewFlushed+1}),
-
-    State1 = ?update_max_time(?diff_time(T1,_T0),State),
-    State2 = ?update_max_qlen(_QLen1,State1),
-    {dropped,?update_other(flushed,FLUSHED,NewFlushed,
-                           State2#{mode => ?set_mode(ModeTab,async),
-                                   last_qlen => 0,
-                                   last_log_ts => T1})}.
-
-%% this clause is called to write to file
-write(Name, Mode, T1, Bin, _CallOrCast,
-      State = #{module := Module,
-                handler_state := HandlerState,
-                mode_tab := ModeTab,
-                ctrl_sync_count := CtrlSync,
-                last_qlen := LastQLen,
-                last_log_ts := T0}) ->
-    %% check if we need to limit the number of writes
-    %% during a burst of log events
-    {DoWrite,State1} = limit_burst(State),
-
-    %% only log synhrounously every ?CONTROLLER_SYNC_INTERVAL time, to
-    %% give the handler time between writes so it can keep up with
-    %% incoming messages
-    {Result,LastQLen1,HandlerState1} =
-        if DoWrite, CtrlSync == 0 ->
-                ?observe(Name,{_CallOrCast,1}),
-                {_,HS1} = Module:write(Name, sync, Bin, HandlerState),
-                {ok,element(2, process_info(self(), message_queue_len)),HS1};
-           DoWrite ->
-                ?observe(Name,{_CallOrCast,1}),
-                {_,HS1} = Module:write(Name, async, Bin, HandlerState),
-                {ok,LastQLen,HS1};
-           not DoWrite ->
-                ?observe(Name,{flushed,1}),
-                {dropped,LastQLen,HandlerState}
-        end,
-
-    %% Check if the time since the previous log event is long enough -
-    %% and the queue length small enough - to assume the mailbox has
-    %% been emptied, and if so, do filesync operation and reset mode to
-    %% async. Note that this is the best we can do to detect an idle
-    %% handler without setting a timer after each log call/cast. If the
-    %% time between two consecutive log events is fast and no new
-    %% event comes in after the last one, idle state won't be detected!
-    Time = ?diff_time(T1,T0),
-    State2 =
-        if (LastQLen1 < ?FILESYNC_OK_QLEN) andalso
-           (Time > ?IDLE_DETECT_TIME_USEC) ->
-                {_,HS2} = Module:filesync(Name,async,HandlerState),
-                State1#{mode => ?change_mode(ModeTab, Mode, async),
-                        burst_msg_count => 0,
-                        handler_state => HS2};
-           true ->
-                State1#{mode => Mode, handler_state => HandlerState1}
-        end,
-    State3 = ?update_calls_or_casts(_CallOrCast,1,State2),
-    State4 = ?update_max_qlen(LastQLen1,State3),
-    State5 =
-        ?update_max_time(Time,
-                         State4#{last_qlen := LastQLen1,
-                                 last_log_ts => T1,
-                                 last_op => write,
-                                 ctrl_sync_count =>
-                                     if CtrlSync==0 -> ?CONTROLLER_SYNC_INTERVAL;
-                                        true -> CtrlSync-1
-                                     end}),
-    {Result,State5}.
+                     [Name,Flushed], State);
+notify(restart,#{id:=Name}=State) ->
+    log_handler_info(Name, "Handler ~p restarted", [Name], State);
+notify(idle,#{id:=Name,module:=Module,handler_state:=HandlerState}=State) ->
+    {_,HS} = Module:filesync(Name,async,HandlerState),
+    State#{handler_state=>HS, last_op=>sync}.
 
 log_handler_info(Name, Format, Args, #{module:=Module,
-                                       formatter:=Formatter,
-                                       handler_state:=HandlerState}) ->
-    Config = #{formatter=>Formatter},
+                                       handler_state:=HandlerState}=State) ->
+    Config =
+        case logger:get_handler_config(Name) of
+            {ok,Conf} -> Conf;
+            _ -> #{formatter=>{?DEFAULT_FORMATTER,?DEFAULT_FORMAT_CONFIG}}
+        end,
     Meta = #{time=>erlang:system_time(microsecond)},
     Bin = log_to_binary(#{level => notice,
                           msg => {Format,Args},
                           meta => Meta}, Config),
-    _ = Module:write(Name, async, Bin, HandlerState),
-    ok.
+    {_,HS} = Module:write(Name, async, Bin, HandlerState),
+    State#{handler_state=>HS, last_op=>write}.
 
 %%%-----------------------------------------------------------------
 %%% Convert log data on any form to binary
@@ -540,42 +416,8 @@ string_to_binary(String) ->
 %%%-----------------------------------------------------------------
 %%% Check that the configuration term is valid
 check_config(Config) when is_map(Config) ->
-    case check_common_config(maps:to_list(Config)) of
-        ok ->
-            case overload_levels_ok(Config) of
-                true ->
-                    ok;
-                false ->
-                    Faulty = maps:with([sync_mode_qlen,
-                                        drop_mode_qlen,
-                                        flush_qlen],Config),
-                    {error,{invalid_levels,Faulty}}
-            end;
-        Error ->
-            Error
-    end.
+    check_common_config(maps:to_list(Config)).
 
-check_common_config([{sync_mode_qlen,N}|Config]) when is_integer(N) ->
-    check_common_config(Config);
-check_common_config([{drop_mode_qlen,N}|Config]) when is_integer(N) ->
-    check_common_config(Config);
-check_common_config([{flush_qlen,N}|Config]) when is_integer(N) ->
-    check_common_config(Config);
-check_common_config([{burst_limit_enable,Bool}|Config]) when is_boolean(Bool) ->
-    check_common_config(Config);
-check_common_config([{burst_limit_max_count,N}|Config]) when is_integer(N) ->
-    check_common_config(Config);
-check_common_config([{burst_limit_window_time,N}|Config]) when is_integer(N) ->
-    check_common_config(Config);
-check_common_config([{overload_kill_enable,Bool}|Config]) when is_boolean(Bool) ->
-    check_common_config(Config);
-check_common_config([{overload_kill_qlen,N}|Config]) when is_integer(N) ->
-    check_common_config(Config);
-check_common_config([{overload_kill_mem_size,N}|Config]) when is_integer(N) ->
-    check_common_config(Config);
-check_common_config([{overload_kill_restart_after,NorA}|Config])
-  when is_integer(NorA); NorA == infinity ->
-    check_common_config(Config);
 check_common_config([{filesync_repeat_interval,NorA}|Config])
   when is_integer(NorA); NorA == no_repeat ->
     check_common_config(Config);
@@ -585,156 +427,7 @@ check_common_config([]) ->
     ok.
 
 get_default_config() ->
-    #{sync_mode_qlen              => ?SYNC_MODE_QLEN,
-      drop_mode_qlen              => ?DROP_MODE_QLEN,
-      flush_qlen                  => ?FLUSH_QLEN,
-      burst_limit_enable          => ?BURST_LIMIT_ENABLE,
-      burst_limit_max_count       => ?BURST_LIMIT_MAX_COUNT,
-      burst_limit_window_time     => ?BURST_LIMIT_WINDOW_TIME,
-      overload_kill_enable        => ?OVERLOAD_KILL_ENABLE,
-      overload_kill_qlen          => ?OVERLOAD_KILL_QLEN,
-      overload_kill_mem_size      => ?OVERLOAD_KILL_MEM_SIZE,
-      overload_kill_restart_after => ?OVERLOAD_KILL_RESTART_AFTER,
-      filesync_repeat_interval    => ?FILESYNC_REPEAT_INTERVAL}.
-
-%%%-----------------------------------------------------------------
-%%% Overload Protection
-call_cast_or_drop(_Name, HandlerPid, ModeTab, Bin) ->
-    %% If the handler process is getting overloaded, the log event
-    %% will be synchronous instead of asynchronous (slows down the
-    %% logging tempo of a process doing lots of logging. If the
-    %% handler is choked, drop mode is set and no event will be sent.
-    try ?get_mode(ModeTab) of
-        async ->
-            gen_server:cast(HandlerPid, {log,Bin});
-        sync ->
-            case call(HandlerPid, {log,Bin}) of
-                ok ->
-                    ok;
-                _Other ->
-                    %% dropped or {error,handler_busy}
-                    ?observe(_Name,{dropped,1}),
-                    ok
-            end;
-        drop ->
-            ?observe(_Name,{dropped,1})
-    catch
-        %% if the ETS table doesn't exist (maybe because of a
-        %% handler restart), we can only drop the event
-        _:_ -> ?observe(_Name,{dropped,1})
-    end,
-    ok.
-
-set_restart_flag(#{id := Name, module := Module} = State) ->
-    log_handler_info(Name, "Handler ~p overloaded and stopping", [Name], State),
-    Flag = list_to_atom(lists:concat([Module,"_",Name,"_restarting"])),
-    spawn(fun() ->
-                  register(Flag, self()),
-                  timer:sleep(infinity)
-          end),
-    ok.
-
-unset_restart_flag(#{id := Name, module := Module} = State) ->
-    Flag = list_to_atom(lists:concat([Module,"_",Name,"_restarting"])),
-    case whereis(Flag) of
-        undefined ->
-            ok;
-        Pid ->
-            exit(Pid, kill),
-            log_handler_info(Name, "Handler ~p restarted", [Name], State)
-    end.
-
-check_load(State = #{id:=_Name, mode_tab := ModeTab, mode := Mode,
-                     sync_mode_qlen := SyncModeQLen,
-                     drop_mode_qlen := DropModeQLen,
-                     flush_qlen := FlushQLen}) ->
-    {_,Mem} = process_info(self(), memory),
-    ?observe(_Name,{max_mem,Mem}),
-    {_,QLen} = process_info(self(), message_queue_len),
-    ?observe(_Name,{max_qlen,QLen}),
-    %% When the handler process gets scheduled in, it's impossible
-    %% to predict the QLen. We could jump "up" arbitrarily from say
-    %% async to sync, async to drop, sync to flush, etc. However, when
-    %% the handler process manages the log events (without flushing),
-    %% one after the other, we will move "down" from drop to sync and
-    %% from sync to async. This way we don't risk getting stuck in
-    %% drop or sync mode with an empty mailbox.
-    {Mode1,_NewDrops,_NewFlushes} =
-        if
-            QLen >= FlushQLen ->
-                {flush, 0,1};
-            QLen >= DropModeQLen ->
-                %% Note that drop mode will force log events to
-                %% be dropped on the client side (never sent get to
-                %% the handler).
-                IncDrops = if Mode == drop -> 0; true -> 1 end,
-                {?change_mode(ModeTab, Mode, drop), IncDrops,0};
-            QLen >= SyncModeQLen ->
-                {?change_mode(ModeTab, Mode, sync), 0,0};
-            true ->
-                {?change_mode(ModeTab, Mode, async), 0,0}
-        end,
-    State1 = ?update_other(drops,DROPS,_NewDrops,State),
-    {Mode1, QLen, Mem,
-     ?update_other(flushes,FLUSHES,_NewFlushes,
-                   State1#{last_qlen => QLen})}.
-
-limit_burst(#{burst_limit_enable := false}=State) ->
-     {true,State};
-limit_burst(#{burst_win_ts := BurstWinT0,
-              burst_msg_count := BurstMsgCount,
-              burst_limit_window_time := BurstLimitWinTime,
-              burst_limit_max_count := BurstLimitMaxCnt} = State) ->
-    if (BurstMsgCount >= BurstLimitMaxCnt) -> 
-            %% the limit for allowed messages has been reached
-            BurstWinT1 = ?timestamp(),
-            case ?diff_time(BurstWinT1,BurstWinT0) of
-                BurstCheckTime when BurstCheckTime < (BurstLimitWinTime*1000) ->
-                    %% we're still within the burst time frame
-                    {false,?update_other(burst_drops,BURSTS,1,State)};
-                _BurstCheckTime ->
-                    %% burst time frame passed, reset counters
-                    {true,State#{burst_win_ts => BurstWinT1,
-                                 burst_msg_count => 0}}
-            end;
-       true ->
-            %% the limit for allowed messages not yet reached
-            {true,State#{burst_win_ts => BurstWinT0,
-                         burst_msg_count => BurstMsgCount+1}}
-    end.
-
-kill_if_choked(Name, QLen, Mem, State = #{overload_kill_enable   := KillIfOL,
-                                          overload_kill_qlen     := OLKillQLen,
-                                          overload_kill_mem_size := OLKillMem}) ->
-    if KillIfOL andalso
-       ((QLen > OLKillQLen) orelse (Mem > OLKillMem)) ->
-            set_restart_flag(State),
-            exit({shutdown,{overloaded,Name,QLen,Mem}});
-       true ->
-            ok
-    end.
-
-flush_log_events(Limit) ->
-    process_flag(priority, high),
-    Flushed = flush_log_events(0, Limit),
-    process_flag(priority, normal),
-    Flushed.
-
-flush_log_events(Limit, Limit) ->
-    Limit;
-flush_log_events(N, Limit) ->
-    %% flush log events but leave other events, such as
-    %% filesync, info and change_config, so that these
-    %% have a chance to be processed even under heavy load
-    receive
-        {'$gen_cast',{log,_}} ->
-            flush_log_events(N+1, Limit);
-        {'$gen_call',{Pid,MRef},{log,_}} ->
-            Pid ! {MRef, dropped},
-            flush_log_events(N+1, Limit)
-    after
-        0 -> N
-    end.
+    #{filesync_repeat_interval => ?FILESYNC_REPEAT_INTERVAL}.
 
 set_repeated_filesync(#{filesync_repeat_interval:=FSyncInt} = State)
   when is_integer(FSyncInt) ->
@@ -752,51 +445,12 @@ cancel_repeated_filesync(State) ->
         error ->
             State
     end.
-
-stop_or_restart(Name, {shutdown,Reason={overloaded,_Name,_QLen,_Mem}},
-                #{overload_kill_restart_after := RestartAfter}) ->
-    %% If we're terminating because of an overload situation (see
-    %% kill_if_choked/4), we need to remove the handler and set a
-    %% restart timer. A separate process must perform this in order to
-    %% avoid deadlock.
-    HandlerPid = self(),
-    ConfigResult = logger:get_handler_config(Name),
-    RemoveAndRestart =
-        fun() ->
-                MRef = erlang:monitor(process, HandlerPid),
-                receive
-                    {'DOWN',MRef,_,_,_} ->
-                        ok
-                after 30000 ->
-                        error_notify(Reason),
-                        exit(HandlerPid, kill)
-                end,
-                case ConfigResult of
-                    {ok,#{module:=HMod}=HConfig0} when is_integer(RestartAfter) ->
-                        _ = logger:remove_handler(Name),
-                        HConfig = try HMod:filter_config(HConfig0)
-                                  catch _:_ -> HConfig0
-                                  end,
-                        _ = timer:apply_after(RestartAfter, logger, add_handler,
-                                              [Name,HMod,HConfig]);
-                    {ok,_} ->
-                        _ = logger:remove_handler(Name);
-                    {error,CfgReason} when is_integer(RestartAfter) ->
-                        error_notify({Name,restart_impossible,CfgReason});
-                    {error,_} ->
-                        ok
-                end
-        end,
-    spawn(RemoveAndRestart),
-    ok;
-stop_or_restart(_Name, _Reason, _State) ->
-    ok.
-
-overload_levels_ok(HandlerConfig) ->
-    SMQL = maps:get(sync_mode_qlen, HandlerConfig, ?SYNC_MODE_QLEN),
-    DMQL = maps:get(drop_mode_qlen, HandlerConfig, ?DROP_MODE_QLEN),
-    FQL = maps:get(flush_qlen, HandlerConfig, ?FLUSH_QLEN),
-    (DMQL > 1) andalso (SMQL =< DMQL) andalso (DMQL =< FQL).
-
 error_notify(Term) ->
     ?internal_log(error, Term).
+
+maybe_set_repeated_filesync(_Olp,
+                            #{filesync_repeat_interval:=FSyncInt},
+                            #{filesync_repeat_interval:=FSyncInt}) ->
+    ok;
+maybe_set_repeated_filesync(Olp,_,#{filesync_repeat_interval:=FSyncInt}) ->
+    logger_olp:cast(Olp,{set_repeated_filesync,FSyncInt}).
diff --git a/lib/kernel/src/logger_h_common.hrl b/lib/kernel/src/logger_h_common.hrl
index 261b0a6246..004a61d9d9 100644
--- a/lib/kernel/src/logger_h_common.hrl
+++ b/lib/kernel/src/logger_h_common.hrl
@@ -1,50 +1,22 @@
-
-%%%-----------------------------------------------------------------
-%%% Overload protection configuration
-
-%%! *** NOTE *** 
-%%! It's important that:
-%%! SYNC_MODE_QLEN =< DROP_MODE_QLEN =< FLUSH_QLEN
-%%! and that DROP_MODE_QLEN >= 2.
-%%! Otherwise the handler could end up in drop mode with no new
-%%! log requests to process. This would cause all future requests
-%%! to be dropped (no switch to async mode would ever take place).
-
-%% This specifies the message_queue_len value where the log
-%% requests switch from asynchronous casts to synchronous calls.
--define(SYNC_MODE_QLEN, 10).
-%% Above this message_queue_len, log requests will be dropped,
-%% i.e. no log requests get sent to the handler process.
--define(DROP_MODE_QLEN, 200).
-%% Above this message_queue_len, the handler process will flush
-%% its mailbox and only leave this number of messages in it.
--define(FLUSH_QLEN, 1000).
-
-%% Never flush more than this number of messages in one go,
-%% or the handler will be unresponsive for seconds (keep this
-%% number as large as possible or the mailbox could grow large).
--define(FLUSH_MAX_N, 5000).
-
-%% BURST_LIMIT_MAX_COUNT is the max number of log requests allowed
-%% to be written within a BURST_LIMIT_WINDOW_TIME time frame.
--define(BURST_LIMIT_ENABLE, true).
--define(BURST_LIMIT_MAX_COUNT, 500).
--define(BURST_LIMIT_WINDOW_TIME, 1000).
-
-%% This enables/disables the feature to automatically get the
-%% handler terminated if it gets too loaded (and can't keep up).
--define(OVERLOAD_KILL_ENABLE, false).
-%% If the message_queue_len goes above this size even after
-%% flushing has been performed, the handler is terminated.
--define(OVERLOAD_KILL_QLEN, 20000).
-%% If the memory usage exceeds this level
--define(OVERLOAD_KILL_MEM_SIZE, 3000000).
-
-%% This is the default time that the handler will wait before
-%% restarting and accepting new requests. The value 'infinity'
-%% disables restarts.
--define(OVERLOAD_KILL_RESTART_AFTER, 5000).
-%%-define(OVERLOAD_KILL_RESTART_AFTER, infinity).
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 1997-2015. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
 
 %% The handler sends asynchronous write requests to the process
 %% controlling the i/o device, but every once in this interval
@@ -65,12 +37,6 @@
 -define(FILESYNC_REPEAT_INTERVAL, 5000).
 %%-define(FILESYNC_REPEAT_INTERVAL, no_repeat).
 
-%% This is the time after last message received that we think/hope
-%% that the handler has an empty mailbox (no new log request has
-%% come in).
--define(IDLE_DETECT_TIME_MSEC, 100).
--define(IDLE_DETECT_TIME_USEC, 100000).
-
 %% Default disk log option values
 -define(DISK_LOG_TYPE, wrap).
 -define(DISK_LOG_MAX_NO_FILES, 10).
@@ -83,43 +49,6 @@
         list_to_atom(lists:concat([MODULE,"_",Name]))).
 
 %%%-----------------------------------------------------------------
-%%% Overload protection macros
-
--define(timestamp(), erlang:monotonic_time(microsecond)).
-
--define(get_mode(Tid),
-        case ets:lookup(Tid, mode) of
-            [{mode,M}] -> M;
-            _          -> async
-        end).
-
--define(set_mode(Tid, M),
-        begin ets:insert(Tid, {mode,M}), M end).
-
--define(change_mode(Tid, M0, M1),
-        if M0 == M1 ->
-                M0;
-           true ->
-                ets:insert(Tid, {mode,M1}),
-                M1
-        end).
-
--define(min(X1, X2),
-        if X2 == undefined -> X1;
-           X2 < X1 -> X2;
-           true -> X1
-        end).
-
--define(max(X1, X2),
-        if 
-            X2 == undefined -> X1;
-            X2 > X1 -> X2;
-            true -> X1
-        end).
-
--define(diff_time(OS_T1, OS_T0), OS_T1-OS_T0).
-
-%%%-----------------------------------------------------------------
 %%% The test hook macros make it possible to observe and manipulate
 %%% internal handler functionality. When enabled, these macros will
 %%% slow down execution and therefore should not be include in code
@@ -183,7 +112,6 @@
               [{_,ERROR}] -> ERROR
           catch _:_       -> disk_log:sync(LOG) end).
 
-  -define(DEFAULT_CALL_TIMEOUT, 5000).
 
 -else.                                          % DEFAULTS!
   -define(TEST_HOOKS_TAB, undefined).
@@ -196,68 +124,4 @@
   -define(file_datasync(DEVICE), file:datasync(DEVICE)).
   -define(disk_log_write(LOG, MODE, DATA), disk_log_write(LOG, MODE, DATA)).
   -define(disk_log_sync(LOG), disk_log:sync(LOG)).
-  -define(DEFAULT_CALL_TIMEOUT, 10000).
--endif.
-
-%%%-----------------------------------------------------------------
-%%% These macros enable statistics counters in the state of the
-%%% handler which is useful for analysing the overload protection
-%%% behaviour. These counters should not be included in code to be
-%%% officially released (as some counters will grow very large
-%%% over time).
-
-%%-define(SAVE_STATS, true).
--ifdef(SAVE_STATS).
-  -define(merge_with_stats(STATE),
-          STATE#{flushes => 0, flushed => 0, drops => 0,
-                 burst_drops => 0, casts => 0, calls => 0,
-                 max_qlen => 0, max_time => 0}).
-
-  -define(update_max_qlen(QLEN, STATE),
-          begin #{max_qlen := QLEN0} = STATE,
-                STATE#{max_qlen => ?max(QLEN0,QLEN)} end).
-
-  -define(update_calls_or_casts(CALL_OR_CAST, INC, STATE),
-          case CALL_OR_CAST of
-              cast ->
-                  #{casts := CASTS0} = STATE,
-                  STATE#{casts => CASTS0+INC};
-              call ->
-                  #{calls := CALLS0} = STATE,
-                  STATE#{calls => CALLS0+INC}
-          end).
-
-  -define(update_max_time(TIME, STATE),
-          begin #{max_time := TIME0} = STATE,
-                STATE#{max_time => ?max(TIME0,TIME)} end).
-
-  -define(update_other(OTHER, VAR, INCVAL, STATE),
-          begin #{OTHER := VAR} = STATE,
-                STATE#{OTHER => VAR+INCVAL} end).
-          
--else.                                          % DEFAULT!
-  -define(merge_with_stats(STATE), STATE).
-  -define(update_max_qlen(_QLEN, STATE), STATE).
-  -define(update_calls_or_casts(_CALL_OR_CAST, _INC, STATE), STATE).
-  -define(update_max_time(_TIME, STATE), STATE).
-  -define(update_other(_OTHER, _VAR, _INCVAL, STATE), STATE).
--endif.
-
-%%%-----------------------------------------------------------------
-%%% These macros enable callbacks that make it possible to analyse
-%%% the overload protection behaviour from outside the handler
-%%% process (including dropped requests on the client side).
-%%% An external callback module (?OBSERVER_MOD) is required which
-%%% is not part of the kernel application. For this reason, these
-%%% callbacks should not be included in code to be officially released.
-
-%%-define(OBSERVER_MOD, logger_test).
--ifdef(OBSERVER_MOD).
-  -define(start_observation(NAME), ?OBSERVER:start_observation(NAME)).
-  -define(observe(NAME,EVENT), ?OBSERVER:observe(NAME,EVENT)).
-
--else.                                          % DEFAULT!
-  -define(start_observation(_NAME), ok).
-  -define(observe(_NAME,_EVENT), ok).
 -endif.
-%%! <---
diff --git a/lib/kernel/src/logger_internal.hrl b/lib/kernel/src/logger_internal.hrl
index d96a4ac78b..e53922e5d3 100644
--- a/lib/kernel/src/logger_internal.hrl
+++ b/lib/kernel/src/logger_internal.hrl
@@ -19,6 +19,7 @@
 %%
 -include_lib("kernel/include/logger.hrl").
 -define(LOGGER_TABLE,logger).
+-define(PROXY_KEY,'$proxy_config$').
 -define(PRIMARY_KEY,'$primary_config$').
 -define(HANDLER_KEY,'$handler_config$').
 -define(LOGGER_META_KEY,'$logger_metadata$').
@@ -40,12 +41,14 @@
 
 -define(DEFAULT_LOGGER_CALL_TIMEOUT, infinity).
 
--define(LOG_INTERNAL(Level,Report),
+-define(LOG_INTERNAL(Level,Report),?DO_LOG_INTERNAL(Level,[Report])).
+-define(LOG_INTERNAL(Level,Format,Args),?DO_LOG_INTERNAL(Level,[Format,Args])).
+-define(DO_LOG_INTERNAL(Level,Data),
         case logger:allow(Level,?MODULE) of
             true ->
                 %% Spawn this to avoid deadlocks
-                _ = spawn(logger,macro_log,[?LOCATION,Level,Report,
-                                            logger:add_default_metadata(#{})]),
+                _ = spawn(logger,macro_log,[?LOCATION,Level|Data]++
+                              [logger:add_default_metadata(#{})]),
                 ok;
             false ->
                 ok
diff --git a/lib/kernel/src/logger_olp.erl b/lib/kernel/src/logger_olp.erl
new file mode 100644
index 0000000000..009280a9c9
--- /dev/null
+++ b/lib/kernel/src/logger_olp.erl
@@ -0,0 +1,626 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2017-2018. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+-module(logger_olp).
+-behaviour(gen_server).
+
+-include("logger_olp.hrl").
+-include("logger_internal.hrl").
+
+%% API
+-export([start_link/4, load/2, info/1, reset/1, stop/1, restart/1,
+         set_opts/2, get_opts/1, get_default_opts/0, get_pid/1,
+         call/2, cast/2, get_ref/0, get_ref/1]).
+
+%% gen_server and proc_lib callbacks
+-export([init/1, handle_call/3, handle_cast/2, handle_info/2,
+         terminate/2, code_change/3]).
+
+-define(OPT_KEYS,[sync_mode_qlen,
+                  drop_mode_qlen,
+                  flush_qlen,
+                  burst_limit_enable,
+                  burst_limit_max_count,
+                  burst_limit_window_time,
+                  overload_kill_enable,
+                  overload_kill_qlen,
+                  overload_kill_mem_size,
+                  overload_kill_restart_after]).
+
+-export_type([olp_ref/0, options/0]).
+
+-opaque olp_ref() :: {atom(),pid(),ets:tid()}.
+
+-type options() :: logger:olp_config().
+
+%%%-----------------------------------------------------------------
+%%% API
+
+-spec start_link(Name,Module,Args,Options) -> {ok,Pid,Olp} | {error,Reason} when
+      Name :: atom(),
+      Module :: module(),
+      Args :: term(),
+      Options :: options(),
+      Pid :: pid(),
+      Olp :: olp_ref(),
+      Reason :: term().
+start_link(Name,Module,Args,Options0) when is_map(Options0) ->
+    Options = maps:merge(get_default_opts(),Options0),
+    case check_opts(Options) of
+        ok ->
+            proc_lib:start_link(?MODULE,init,[[Name,Module,Args,Options]]);
+        Error ->
+            Error
+    end.
+
+-spec load(Olp, Msg) -> ok when
+      Olp :: olp_ref(),
+      Msg :: term().
+load({_Name,Pid,ModeRef},Msg) ->
+    %% If the process is getting overloaded, the message will be
+    %% synchronous instead of asynchronous (slows down the tempo of a
+    %% process causing much load). If the process is choked, drop mode
+    %% is set and no message is sent.
+    try ?get_mode(ModeRef) of
+        async ->
+            gen_server:cast(Pid, {'$olp_load',Msg});
+        sync ->
+            case call(Pid, {'$olp_load',Msg}) of
+                ok ->
+                    ok;
+                _Other ->
+                    %% dropped or {error,busy}
+                    ?observe(_Name,{dropped,1}),
+                    ok
+            end;
+        drop ->
+            ?observe(_Name,{dropped,1})
+    catch
+        %% if the ETS table doesn't exist (maybe because of a
+        %% process restart), we can only drop the event
+        _:_ -> ?observe(_Name,{dropped,1})
+    end,
+    ok.    
+
+-spec info(Olp) -> map() | {error, busy} when
+      Olp :: atom() | pid() | olp_ref().
+info(Olp) ->
+    call(Olp, info).
+
+-spec reset(Olp) -> ok | {error, busy} when
+      Olp :: atom() | pid() | olp_ref().
+reset(Olp) ->
+    call(Olp, reset).
+
+-spec stop(Olp) -> ok when
+      Olp :: atom() | pid() | olp_ref().
+stop({_Name,Pid,_ModRef}) ->
+    stop(Pid);
+stop(Pid) ->
+    _ = gen_server:call(Pid, stop),
+    ok.
+
+-spec set_opts(Olp, Opts) -> ok | {error,term()} | {error, busy} when
+      Olp :: atom() | pid() | olp_ref(),
+      Opts :: options().
+set_opts(Olp, Opts) ->
+    call(Olp, {set_opts,Opts}).
+
+-spec get_opts(Olp) -> options() | {error, busy} when
+      Olp :: atom() | pid() | olp_ref().
+get_opts(Olp) ->
+    call(Olp, get_opts).
+
+-spec get_default_opts() -> options().
+get_default_opts() ->
+    #{sync_mode_qlen              => ?SYNC_MODE_QLEN,
+      drop_mode_qlen              => ?DROP_MODE_QLEN,
+      flush_qlen                  => ?FLUSH_QLEN,
+      burst_limit_enable          => ?BURST_LIMIT_ENABLE,
+      burst_limit_max_count       => ?BURST_LIMIT_MAX_COUNT,
+      burst_limit_window_time     => ?BURST_LIMIT_WINDOW_TIME,
+      overload_kill_enable        => ?OVERLOAD_KILL_ENABLE,
+      overload_kill_qlen          => ?OVERLOAD_KILL_QLEN,
+      overload_kill_mem_size      => ?OVERLOAD_KILL_MEM_SIZE,
+      overload_kill_restart_after => ?OVERLOAD_KILL_RESTART_AFTER}.
+
+-spec restart(fun(() -> any())) -> ok.
+restart(Fun) ->
+    Result =
+        try Fun()
+        catch C:R:S ->
+                {error,{restart_failed,Fun,C,R,S}}
+        end,
+    ?LOG_INTERNAL(debug,[{logger_olp,restart},
+                         {result,Result}]),
+    ok.
+
+-spec get_ref() -> olp_ref().
+get_ref() ->
+    get(olp_ref).
+
+-spec get_ref(PidOrName) -> olp_ref() | {error, busy} when
+      PidOrName :: pid() | atom().
+get_ref(PidOrName) ->
+    call(PidOrName,get_ref).
+
+-spec get_pid(olp_ref()) -> pid().
+get_pid({_Name,Pid,_ModeRef}) ->
+    Pid.
+
+%%%===================================================================
+%%% gen_server callbacks
+%%%===================================================================
+
+init([Name,Module,Args,Options]) ->
+    register(Name, self()),
+    process_flag(message_queue_data, off_heap),
+
+    ?start_observation(Name),
+
+    try ets:new(Name, [public]) of
+        ModeRef ->
+            OlpRef = {Name,self(),ModeRef},
+            put(olp_ref,OlpRef),
+            try Module:init(Args) of
+                {ok,CBState} ->
+                    ?set_mode(ModeRef, async),
+                    T0 = ?timestamp(),
+                    proc_lib:init_ack({ok,self(),OlpRef}),
+                    %% Storing options in state to avoid copying
+                    %% (sending) the option data with each message
+                    State0 = ?merge_with_stats(
+                                Options#{id => Name,
+                                         idle=> true,
+                                         module => Module,
+                                         mode_ref => ModeRef,
+                                         mode => async,
+                                         last_qlen => 0,
+                                         last_load_ts => T0,
+                                         burst_win_ts => T0,
+                                         burst_msg_count => 0,
+                                         cb_state => CBState}),
+                    State = reset_restart_flag(State0),
+                    gen_server:enter_loop(?MODULE, [], State);
+                Error ->
+                    _ = ets:delete(ModeRef),
+                    unregister(Name),
+                    proc_lib:init_ack(Error)
+            catch
+                _:Error ->
+                    _ = ets:delete(ModeRef),
+                    unregister(Name),
+                    proc_lib:init_ack(Error)
+            end
+    catch
+        _:Error ->
+            unregister(Name),
+            proc_lib:init_ack(Error)
+    end.
+
+%% This is the synchronous load event.
+handle_call({'$olp_load', Msg}, _From, State) ->
+    {Result,State1} = do_load(Msg, call, State#{idle=>false}),
+    %% Result == ok | dropped
+    reply_return(Result,State1);
+
+handle_call(get_ref,_From,#{id:=Name,mode_ref:=ModeRef}=State) ->
+    reply_return({Name,self(),ModeRef},State);
+
+handle_call({set_opts,Opts0},_From,State) ->
+    Opts = maps:merge(maps:with(?OPT_KEYS,State),Opts0),
+    case check_opts(Opts) of
+        ok ->
+            reply_return(ok, maps:merge(State,Opts));
+        Error ->
+            reply_return(Error, State)
+    end;
+
+handle_call(get_opts,_From,State) ->
+    reply_return(maps:with(?OPT_KEYS,State), State);
+
+handle_call(info, _From, State) ->
+    reply_return(State, State);
+
+handle_call(reset, _From, #{module:=Module,cb_state:=CBState}=State) ->
+    State1 = ?merge_with_stats(State),
+    CBState1 = try_callback_call(Module,reset_state,[CBState],CBState),
+    reply_return(ok, State1#{idle => true,
+                             last_qlen => 0,
+                             last_load_ts => ?timestamp(),
+                             cb_state => CBState1});
+
+handle_call(stop, _From, State) ->
+    {stop, {shutdown,stopped}, ok, State};
+
+handle_call(Msg, From, #{module:=Module,cb_state:=CBState}=State) ->
+    case try_callback_call(Module,handle_call,[Msg, From, CBState]) of
+        {reply,Reply,CBState1} ->
+            reply_return(Reply,State#{cb_state=>CBState1});
+        {noreply,CBState1} ->
+            noreply_return(State#{cb_state=>CBState1});
+        {stop, Reason, Reply, CBState1} ->
+            {stop, Reason, Reply, State#{cb_state=>CBState1}};
+        {stop, Reason, CBState1} ->
+            {stop, Reason, State#{cb_state=>CBState1}}
+    end.
+
+%% This is the asynchronous load event.
+handle_cast({'$olp_load', Msg}, State) ->
+    {_Result,State1} = do_load(Msg, cast, State#{idle=>false}),
+    noreply_return(State1);
+
+handle_cast(Msg, #{module:=Module, cb_state:=CBState} = State) ->
+    case try_callback_call(Module,handle_cast,[Msg, CBState]) of
+        {noreply,CBState1} ->
+            noreply_return(State#{cb_state=>CBState1});
+        {stop, Reason, CBState1} ->
+            {stop, Reason, State#{cb_state=>CBState1}}
+    end.
+
+handle_info(timeout, #{mode_ref:=_ModeRef, mode:=Mode} = State) ->
+    State1 = notify(idle,State),
+    State2 = maybe_notify_mode_change(async,State1),
+    {noreply, State2#{idle => true,
+                      mode => ?change_mode(_ModeRef, Mode, async),
+                      burst_msg_count => 0}};
+handle_info(Msg, #{module := Module, cb_state := CBState} = State) ->
+    case try_callback_call(Module,handle_info,[Msg, CBState]) of
+        {noreply,CBState1} ->
+            noreply_return(State#{cb_state=>CBState1});
+        {stop, Reason, CBState1} ->
+            {stop, Reason, State#{cb_state=>CBState1}};
+        {load,CBState1} ->
+            {_,State1} = do_load(Msg, cast, State#{idle=>false,
+                                                   cb_state=>CBState1}),
+            noreply_return(State1)
+    end.
+
+terminate({shutdown,{overloaded,_QLen,_Mem}},
+          #{id:=Name, module := Module, cb_state := CBState,
+            overload_kill_restart_after := RestartAfter} = State) ->
+    %% We're terminating because of an overload situation (see
+    %% kill_if_choked/3).
+    unregister(Name), %%!!!! to avoid error printout of callback crashed on stop
+    case try_callback_call(Module,terminate,[overloaded,CBState],ok) of
+        {ok,Fun} when is_function(Fun,0), is_integer(RestartAfter) ->
+            set_restart_flag(State),
+            _ = timer:apply_after(RestartAfter,?MODULE,restart,[Fun]),
+            ok;
+        _ ->
+            ok
+    end;
+terminate(Reason, #{id:=Name, module:=Module, cb_state:=CBState}) ->
+    _ = try_callback_call(Module,terminate,[Reason,CBState],ok),
+    unregister(Name),
+    ok.
+
+code_change(_OldVsn, State, _Extra) ->
+    {ok, State}.
+
+
+%%%-----------------------------------------------------------------
+%%% Internal functions
+-spec call(Olp, term()) -> term() | {error,busy} when
+      Olp :: atom() | pid() | olp_ref().
+call({_Name, Pid, _ModeRef},Msg) ->
+    call(Pid, Msg);
+call(Server, Msg) ->
+    try
+        gen_server:call(Server, Msg)
+    catch
+        _:{timeout,_} -> {error,busy}
+    end.
+
+-spec cast(olp_ref(),term()) -> ok.
+cast({_Name, Pid, _ModeRef},Msg) ->
+    gen_server:cast(Pid, Msg).
+
+%% check for overload between every event (and set Mode to async,
+%% sync or drop accordingly), but never flush the whole mailbox
+%% before LogWindowSize events have been handled
+do_load(Msg, CallOrCast, State) ->
+    T1 = ?timestamp(),
+    State1 = ?update_time(T1,State),
+
+    %% check if the process is getting overloaded, or if it's
+    %% recovering from overload (the check must be done for each
+    %% event to react quickly to large bursts of events and
+    %% to ensure that the handler can never end up in drop mode
+    %% with an empty mailbox, which would stop operation)
+    {Mode1,QLen,Mem,State2} = check_load(State1),
+
+    %% kill the handler if it can't keep up with the load
+    kill_if_choked(QLen, Mem, State2),
+
+    if Mode1 == flush ->
+            flush(T1, State2);
+       true ->
+            handle_load(Mode1, T1, Msg, CallOrCast, State2)
+    end.
+
+%% this function is called by do_load/3 after an overload check
+%% has been performed, where QLen > FlushQLen
+flush(T1, State=#{id := _Name, mode := Mode, last_load_ts := _T0, mode_ref := ModeRef}) ->
+    %% flush load messages in the mailbox (a limited number in order
+    %% to not cause long delays)
+    NewFlushed = flush_load(?FLUSH_MAX_N),
+
+    %% write info in log about flushed messages
+    State1=notify({flushed,NewFlushed},State),
+
+    %% because of the receive loop when flushing messages, the
+    %% handler will be scheduled out often and the mailbox could
+    %% grow very large, so we'd better check the queue again here
+    {_,QLen1} = process_info(self(), message_queue_len),
+    ?observe(_Name,{max_qlen,QLen1}),
+
+    %% Add 1 for the current log event
+    ?observe(_Name,{flushed,NewFlushed+1}),
+
+    State2 = ?update_max_time(?diff_time(T1,_T0),State1),
+    State3 = ?update_max_qlen(QLen1,State2),
+    State4 = maybe_notify_mode_change(async,State3),
+    {dropped,?update_other(flushed,FLUSHED,NewFlushed,
+                           State4#{mode => ?change_mode(ModeRef,Mode,async),
+                                   last_qlen => QLen1,
+                                   last_load_ts => T1})}.
+
+%% this function is called to actually handle the message
+handle_load(Mode, T1, Msg, _CallOrCast,
+      State = #{id := _Name,
+                module := Module,
+                cb_state := CBState,
+                last_qlen := LastQLen,
+                last_load_ts := _T0}) ->
+    %% check if we need to limit the number of writes
+    %% during a burst of log events
+    {DoWrite,State1} = limit_burst(State),
+
+    {Result,LastQLen1,CBState1} =
+        if DoWrite ->
+                ?observe(_Name,{_CallOrCast,1}),
+                CBS = try_callback_call(Module,handle_load,[Msg,CBState]),
+                {ok,element(2, process_info(self(), message_queue_len)),CBS};
+           true ->
+                ?observe(_Name,{flushed,1}),
+                {dropped,LastQLen,CBState}
+        end,
+    State2 = State1#{cb_state=>CBState1},
+
+    State3 = State2#{mode => Mode},
+    State4 = ?update_calls_or_casts(_CallOrCast,1,State3),
+    State5 = ?update_max_qlen(LastQLen1,State4),
+    State6 =
+        ?update_max_time(?diff_time(T1,_T0),
+                         State5#{last_qlen := LastQLen1,
+                                 last_load_ts => T1}),
+    State7 = case Result of
+                 ok ->
+                     S = ?update_freq(T1,State6),
+                     ?update_other(writes,WRITES,1,S);
+                 _ ->
+                     State6
+             end,
+    {Result,State7}.
+
+
+%%%-----------------------------------------------------------------
+%%% Check that the options are valid
+check_opts(Options) when is_map(Options) ->
+    case do_check_opts(maps:to_list(Options)) of
+        ok ->
+            case overload_levels_ok(Options) of
+                true ->
+                    ok;
+                false ->
+                    Faulty = maps:with([sync_mode_qlen,
+                                        drop_mode_qlen,
+                                        flush_qlen],Options),
+                    {error,{invalid_olp_levels,Faulty}}
+            end;
+        {error,Key,Value} ->
+            {error,{invalid_olp_config,#{Key=>Value}}}
+    end.
+
+do_check_opts([{sync_mode_qlen,N}|Options]) when is_integer(N) ->
+    do_check_opts(Options);
+do_check_opts([{drop_mode_qlen,N}|Options]) when is_integer(N) ->
+    do_check_opts(Options);
+do_check_opts([{flush_qlen,N}|Options]) when is_integer(N) ->
+    do_check_opts(Options);
+do_check_opts([{burst_limit_enable,Bool}|Options]) when is_boolean(Bool) ->
+    do_check_opts(Options);
+do_check_opts([{burst_limit_max_count,N}|Options]) when is_integer(N) ->
+    do_check_opts(Options);
+do_check_opts([{burst_limit_window_time,N}|Options]) when is_integer(N) ->
+    do_check_opts(Options);
+do_check_opts([{overload_kill_enable,Bool}|Options]) when is_boolean(Bool) ->
+    do_check_opts(Options);
+do_check_opts([{overload_kill_qlen,N}|Options]) when is_integer(N) ->
+    do_check_opts(Options);
+do_check_opts([{overload_kill_mem_size,N}|Options]) when is_integer(N) ->
+    do_check_opts(Options);
+do_check_opts([{overload_kill_restart_after,NorA}|Options])
+  when is_integer(NorA); NorA == infinity ->
+    do_check_opts(Options);
+do_check_opts([{Key,Value}|_]) ->
+    {error,Key,Value};
+do_check_opts([]) ->
+    ok.
+
+set_restart_flag(#{id := Name, module := Module}) ->
+    Flag = list_to_atom(lists:concat([Module,"_",Name,"_restarting"])),
+    spawn(fun() ->
+                  register(Flag, self()),
+                  timer:sleep(infinity)
+          end),
+    ok.
+
+reset_restart_flag(#{id := Name, module := Module} = State) ->
+    Flag = list_to_atom(lists:concat([Module,"_",Name,"_restarting"])),
+    case whereis(Flag) of
+        undefined ->
+            State;
+        Pid ->
+            exit(Pid, kill),
+            notify(restart,State)
+    end.
+
+check_load(State = #{id:=_Name, mode_ref := ModeRef, mode := Mode,
+                     sync_mode_qlen := SyncModeQLen,
+                     drop_mode_qlen := DropModeQLen,
+                     flush_qlen := FlushQLen}) ->
+    {_,Mem} = process_info(self(), memory),
+    ?observe(_Name,{max_mem,Mem}),
+    {_,QLen} = process_info(self(), message_queue_len),
+    ?observe(_Name,{max_qlen,QLen}),
+    %% When the handler process gets scheduled in, it's impossible
+    %% to predict the QLen. We could jump "up" arbitrarily from say
+    %% async to sync, async to drop, sync to flush, etc. However, when
+    %% the handler process manages the log events (without flushing),
+    %% one after the other, we will move "down" from drop to sync and
+    %% from sync to async. This way we don't risk getting stuck in
+    %% drop or sync mode with an empty mailbox.
+    {Mode1,_NewDrops,_NewFlushes} =
+        if
+            QLen >= FlushQLen ->
+                {flush, 0,1};
+            QLen >= DropModeQLen ->
+                %% Note that drop mode will force load messages to
+                %% be dropped on the client side (never sent to
+                %% the olp process).
+                IncDrops = if Mode == drop -> 0; true -> 1 end,
+                {?change_mode(ModeRef, Mode, drop), IncDrops,0};
+            QLen >= SyncModeQLen ->
+                {?change_mode(ModeRef, Mode, sync), 0,0};
+            true ->
+                {?change_mode(ModeRef, Mode, async), 0,0}
+        end,
+    State1 = ?update_other(drops,DROPS,_NewDrops,State),
+    State2 = ?update_max_qlen(QLen,State1),
+    State3 = maybe_notify_mode_change(Mode1,State2),
+    {Mode1, QLen, Mem,
+     ?update_other(flushes,FLUSHES,_NewFlushes,
+                   State3#{last_qlen => QLen})}.
+
+limit_burst(#{burst_limit_enable := false}=State) ->
+     {true,State};
+limit_burst(#{burst_win_ts := BurstWinT0,
+              burst_msg_count := BurstMsgCount,
+              burst_limit_window_time := BurstLimitWinTime,
+              burst_limit_max_count := BurstLimitMaxCnt} = State) ->
+    if (BurstMsgCount >= BurstLimitMaxCnt) -> 
+            %% the limit for allowed messages has been reached
+            BurstWinT1 = ?timestamp(),
+            case ?diff_time(BurstWinT1,BurstWinT0) of
+                BurstCheckTime when BurstCheckTime < (BurstLimitWinTime*1000) ->
+                    %% we're still within the burst time frame
+                    {false,?update_other(burst_drops,BURSTS,1,State)};
+                _BurstCheckTime ->
+                    %% burst time frame passed, reset counters
+                    {true,State#{burst_win_ts => BurstWinT1,
+                                 burst_msg_count => 0}}
+            end;
+       true ->
+            %% the limit for allowed messages not yet reached
+            {true,State#{burst_win_ts => BurstWinT0,
+                         burst_msg_count => BurstMsgCount+1}}
+    end.
+
+kill_if_choked(QLen, Mem, #{overload_kill_enable   := KillIfOL,
+                            overload_kill_qlen     := OLKillQLen,
+                            overload_kill_mem_size := OLKillMem}) ->
+    if KillIfOL andalso
+       ((QLen > OLKillQLen) orelse (Mem > OLKillMem)) ->
+            exit({shutdown,{overloaded,QLen,Mem}});
+       true ->
+            ok
+    end.
+
+flush_load(Limit) ->
+    process_flag(priority, high),
+    Flushed = flush_load(0, Limit),
+    process_flag(priority, normal),
+    Flushed.
+
+flush_load(Limit, Limit) ->
+    Limit;
+flush_load(N, Limit) ->
+    %% flush log events but leave other events, such as info, reset
+    %% and stop, so that these have a chance to be processed even
+    %% under heavy load
+    receive
+        {'$gen_cast',{'$olp_load',_}} ->
+            flush_load(N+1, Limit);
+        {'$gen_call',{Pid,MRef},{'$olp_load',_}} ->
+            Pid ! {MRef, dropped},
+            flush_load(N+1, Limit);
+        {log,_,_,_,_} ->
+            flush_load(N+1, Limit);
+        {log,_,_,_} ->
+            flush_load(N+1, Limit)            
+    after
+        0 -> N
+    end.
+
+overload_levels_ok(Options) ->
+    SMQL = maps:get(sync_mode_qlen, Options, ?SYNC_MODE_QLEN),
+    DMQL = maps:get(drop_mode_qlen, Options, ?DROP_MODE_QLEN),
+    FQL = maps:get(flush_qlen, Options, ?FLUSH_QLEN),
+    (DMQL > 1) andalso (SMQL =< DMQL) andalso (DMQL =< FQL).
+
+maybe_notify_mode_change(drop,#{mode:=Mode0}=State)
+  when Mode0=/=drop ->
+    notify({mode_change,Mode0,drop},State);
+maybe_notify_mode_change(Mode1,#{mode:=drop}=State)
+  when Mode1==async; Mode1==sync ->
+    notify({mode_change,drop,Mode1},State);
+maybe_notify_mode_change(_,State) ->
+    State.
+
+notify(Note,#{module:=Module,cb_state:=CBState}=State) ->
+    CBState1 = try_callback_call(Module,notify,[Note,CBState],CBState),
+    State#{cb_state=>CBState1}.
+
+try_callback_call(Module, Function, Args) ->
+    try_callback_call(Module, Function, Args, '$no_default_return').
+
+try_callback_call(Module, Function, Args, DefRet) ->
+    try apply(Module, Function, Args)
+    catch
+        throw:R -> R;
+        error:undef:S when DefRet=/='$no_default_return' ->
+            case S of
+                [{Module,Function,Args,_}|_] ->
+                    DefRet;
+                _ ->
+                    erlang:raise(error,undef,S)
+            end
+    end.
+
+noreply_return(#{idle:=true}=State) ->
+    {noreply,State};
+noreply_return(#{idle:=false}=State) ->
+    {noreply,State,?IDLE_DETECT_TIME}.
+
+reply_return(Reply,#{idle:=true}=State) ->
+    {reply,Reply,State};
+reply_return(Reply,#{idle:=false}=State) ->
+    {reply,Reply,State,?IDLE_DETECT_TIME}.
diff --git a/lib/kernel/src/logger_olp.hrl b/lib/kernel/src/logger_olp.hrl
new file mode 100644
index 0000000000..9b4f5ebf27
--- /dev/null
+++ b/lib/kernel/src/logger_olp.hrl
@@ -0,0 +1,180 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 1997-2015. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+
+%%%-----------------------------------------------------------------
+%%% Overload protection configuration
+
+%%! *** NOTE *** 
+%%! It's important that:
+%%! SYNC_MODE_QLEN =< DROP_MODE_QLEN =< FLUSH_QLEN
+%%! and that DROP_MODE_QLEN >= 2.
+%%! Otherwise the process could end up in drop mode with no new
+%%! log requests to process. This would cause all future requests
+%%! to be dropped (no switch to async mode would ever take place).
+
+%% This specifies the message_queue_len value where the log
+%% requests switch from asynchronous casts to synchronous calls.
+-define(SYNC_MODE_QLEN, 10).
+%% Above this message_queue_len, log requests will be dropped,
+%% i.e. no log requests get sent to the process.
+-define(DROP_MODE_QLEN, 200).
+%% Above this message_queue_len, the process will flush its mailbox
+%% and only leave this number of messages in it.
+-define(FLUSH_QLEN, 1000).
+
+%% Never flush more than this number of messages in one go, or the
+%% process will be unresponsive for seconds (keep this number as large
+%% as possible or the mailbox could grow large).
+-define(FLUSH_MAX_N, 5000).
+
+%% BURST_LIMIT_MAX_COUNT is the max number of log requests allowed
+%% to be written within a BURST_LIMIT_WINDOW_TIME time frame.
+-define(BURST_LIMIT_ENABLE, true).
+-define(BURST_LIMIT_MAX_COUNT, 500).
+-define(BURST_LIMIT_WINDOW_TIME, 1000).
+
+%% This enables/disables the feature to automatically terminate the
+%% process if it gets too loaded (and can't keep up).
+-define(OVERLOAD_KILL_ENABLE, false).
+%% If the message_queue_len goes above this size even after
+%% flushing has been performed, the process is terminated.
+-define(OVERLOAD_KILL_QLEN, 20000).
+%% If the memory usage exceeds this level, the process is terminated.
+-define(OVERLOAD_KILL_MEM_SIZE, 3000000).
+
+%% This is the default time to wait before restarting and accepting
+%% new requests. The value 'infinity' disables restarts.
+-define(OVERLOAD_KILL_RESTART_AFTER, 5000).
+
+%% This is the time in milliseconds after last load message received
+%% that we notify the callback about being idle.
+-define(IDLE_DETECT_TIME, 100).
+
+%%%-----------------------------------------------------------------
+%%% Overload protection macros
+
+-define(timestamp(), erlang:monotonic_time(microsecond)).
+
+-define(get_mode(Tid),
+        case ets:lookup(Tid, mode) of
+            [{mode,M}] -> M;
+            _          -> async
+        end).
+
+-define(set_mode(Tid, M),
+        begin ets:insert(Tid, {mode,M}), M end).
+
+-define(change_mode(Tid, M0, M1),
+        if M0 == M1 ->
+                M0;
+           true ->
+                ets:insert(Tid, {mode,M1}),
+                M1
+        end).
+
+-define(max(X1, X2),
+        if 
+            X2 == undefined -> X1;
+            X2 > X1 -> X2;
+            true -> X1
+        end).
+
+-define(diff_time(OS_T1, OS_T0), OS_T1-OS_T0).
+
+%%%-----------------------------------------------------------------
+%%% These macros enable statistics counters in the state of the
+%%% process, which is useful for analysing the overload protection
+%%% behaviour. These counters should not be included in code to be
+%%% officially released (as some counters will grow very large over
+%%% time).
+
+%% -define(SAVE_STATS, true).
+-ifdef(SAVE_STATS).
+  -define(merge_with_stats(STATE),
+          begin
+              TIME = ?timestamp(),
+              STATE#{start => TIME, time => {TIME,0},
+                     flushes => 0, flushed => 0, drops => 0,
+                     burst_drops => 0, casts => 0, calls => 0,
+                     writes => 0, max_qlen => 0, max_time => 0,
+                     freq => {TIME,0,0}} end).
+
+  -define(update_max_qlen(QLEN, STATE),
+          begin #{max_qlen := QLEN0} = STATE,
+                STATE#{max_qlen => ?max(QLEN0,QLEN)} end).
+
+  -define(update_calls_or_casts(CALL_OR_CAST, INC, STATE),
+          case CALL_OR_CAST of
+              cast ->
+                  #{casts := CASTS0} = STATE,
+                  STATE#{casts => CASTS0+INC};
+              call ->
+                  #{calls := CALLS0} = STATE,
+                  STATE#{calls => CALLS0+INC}
+          end).
+
+  -define(update_max_time(TIME, STATE),
+          begin #{max_time := TIME0} = STATE,
+                STATE#{max_time => ?max(TIME0,TIME)} end).
+
+  -define(update_other(OTHER, VAR, INCVAL, STATE),
+          begin #{OTHER := VAR} = STATE,
+                STATE#{OTHER => VAR+INCVAL} end).
+
+  -define(update_freq(TIME,STATE),
+          begin
+              case STATE of
+                  #{freq := {START, 49, _}} ->
+                      STATE#{freq => {TIME, 0, trunc(1000000*50/(?diff_time(TIME,START)))}};
+                  #{freq := {START, N, FREQ}} ->
+                      STATE#{freq => {START, N+1, FREQ}}
+              end end).
+
+  -define(update_time(TIME,STATE),
+          begin #{start := START} = STATE,
+                STATE#{time => {TIME,trunc((?diff_time(TIME,START))/1000000)}} end).
+
+-else.                                          % DEFAULT!
+  -define(merge_with_stats(STATE), STATE).
+  -define(update_max_qlen(_QLEN, STATE), STATE).
+  -define(update_calls_or_casts(_CALL_OR_CAST, _INC, STATE), STATE).
+  -define(update_max_time(_TIME, STATE), STATE).
+  -define(update_other(_OTHER, _VAR, _INCVAL, STATE), STATE).
+  -define(update_freq(_TIME, STATE), STATE).
+  -define(update_time(_TIME, STATE), STATE).
+-endif.
+
+%%%-----------------------------------------------------------------
+%%% These macros enable callbacks that make it possible to analyse the
+%%% overload protection behaviour from outside the process (including
+%%% dropped requests on the client side). An external callback module
+%%% (?OBSERVER_MOD) is required which is not part of the kernel
+%%% application. For this reason, these callbacks should not be
+%%% included in code to be officially released.
+
+%%-define(OBSERVER_MOD, logger_test).
+-ifdef(OBSERVER_MOD).
+  -define(start_observation(NAME), ?OBSERVER:start_observation(NAME)).
+  -define(observe(NAME,EVENT), ?OBSERVER:observe(NAME,EVENT)).
+
+-else.                                          % DEFAULT!
+  -define(start_observation(_NAME), ok).
+  -define(observe(_NAME,_EVENT), ok).
+-endif.
diff --git a/lib/kernel/src/logger_proxy.erl b/lib/kernel/src/logger_proxy.erl
new file mode 100644
index 0000000000..24b293805c
--- /dev/null
+++ b/lib/kernel/src/logger_proxy.erl
@@ -0,0 +1,165 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2017-2018. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+-module(logger_proxy).
+
+%% API
+-export([start_link/0, restart/0, log/1, child_spec/0, get_default_config/0]).
+
+%% logger_olp callbacks
+-export([init/1, handle_load/2, handle_info/2, terminate/2,
+         notify/2]).
+
+-include("logger_internal.hrl").
+
+-define(SERVER,?MODULE).
+
+%%%-----------------------------------------------------------------
+%%% API
+-spec log(RemoteLog) -> ok when
+      RemoteLog :: {remote,node(),LogEvent},
+      LogEvent :: {log,Level,Format,Args,Meta} |
+                  {log,Level,StringOrReport,Meta},
+      Level :: logger:level(),
+      Format :: io:format(),
+      Args :: list(term()),
+      StringOrReport :: unicode:chardata() | logger:report(),
+      Meta :: logger:metadata().
+log(RemoteLog) ->
+    Olp = persistent_term:get(?MODULE),
+    case logger_olp:get_pid(Olp) =:= self() of
+        true ->
+            %% This happens when the log event comes from the
+            %% emulator, and the group leader is on a remote node.
+            _ = handle_load(RemoteLog, no_state),
+            ok;
+        false ->
+            logger_olp:load(Olp, RemoteLog)
+    end.
+
+%% Called by supervisor
+-spec start_link() -> {ok,pid(),logger_olp:olp_ref()} | {error,term()}.
+start_link() ->
+    %% Notice that sync_mode is only used when logging to remote node,
+    %% i.e. when the log/2 API function is called.
+    %%
+    %% When receiving log events from the emulator or from a remote
+    %% node, the log event is sent as a message to this process, and
+    %% thus received directly in handle_info/2. This means that the
+    %% mode (async/sync/drop) is not read before the message is
+    %% sent. Thus sync mode is never entered, and drop mode is
+    %% implemented by setting the system_logger flag to undefined (see
+    %% notify/2)
+    %%
+    %% Burst limit is disabled, since this is only a proxy and we
+    %% don't want to limit bursts twice (here and in the handler).
+    logger_olp:start_link(?SERVER,?MODULE,[],logger:get_proxy_config()).
+
+%% Fun used for restarting this process after it has been killed due
+%% to overload (must set overload_kill_enable=>true in opts)
+restart() ->
+    case supervisor:start_child(logger_sup, child_spec()) of
+        {ok,_Pid,Olp} ->
+            {ok,Olp};
+        {error,{Reason,Ch}} when is_tuple(Ch), element(1,Ch)==child ->
+            {error,Reason};
+        Error ->
+            Error
+    end.
+
+%% Called internally and by logger_sup
+child_spec() ->
+    Name = ?SERVER,
+    #{id       => Name,
+      start    => {?MODULE, start_link, []},
+      restart  => temporary,
+      shutdown => 2000,
+      type     => worker,
+      modules  => [?MODULE]}.
+
+get_default_config() ->
+    OlpDefault = logger_olp:get_default_opts(),
+    OlpDefault#{sync_mode_qlen=>500,
+                drop_mode_qlen=>1000,
+                flush_qlen=>5000,
+                burst_limit_enable=>false}.
+
+%%%===================================================================
+%%% gen_server callbacks
+%%%===================================================================
+
+init([]) ->
+    process_flag(trap_exit, true),
+    _ = erlang:system_flag(system_logger,self()),
+    persistent_term:put(?MODULE,logger_olp:get_ref()),
+    {ok,no_state}.
+
+%% Log event to send to the node where the group leader of it's client resides
+handle_load({remote,Node,Log},State) ->
+    %% If the connection is overloaded (send_nosuspend returns false),
+    %% we drop the message.
+    _ = erlang:send_nosuspend({?SERVER,Node},Log),
+    State;
+%% Log event to log on this node
+handle_load({log,Level,Format,Args,Meta},State) ->
+    try_log([Level,Format,Args,Meta]),
+    State;
+handle_load({log,Level,Report,Meta},State) ->
+    try_log([Level,Report,Meta]),
+    State.
+
+%% Log event sent to this process e.g. from the emulator - it is really load
+handle_info(Log,State) when is_tuple(Log), element(1,Log)==log ->
+    {load,State}.
+
+terminate(overloaded, _State) ->
+    _ = erlang:system_flag(system_logger,undefined),
+    {ok,fun ?MODULE:restart/0};
+terminate(_Reason, _State) ->
+    _ = erlang:system_flag(system_logger,whereis(logger)),
+    ok.
+
+notify({mode_change,Mode0,Mode1},State) ->
+    _ = if Mode1=:=drop -> % entering drop mode
+                erlang:system_flag(system_logger,undefined);
+           Mode0=:=drop -> % leaving drop mode
+                erlang:system_flag(system_logger,self());
+           true ->
+                ok
+        end,
+    ?LOG_INTERNAL(notice,"~w switched from ~w to ~w mode",[?MODULE,Mode0,Mode1]),
+    State;
+notify({flushed,Flushed},State) ->
+    ?LOG_INTERNAL(notice, "~w flushed ~w log events",[?MODULE,Flushed]),
+    State;
+notify(restart,State) ->
+    ?LOG_INTERNAL(notice, "~w restarted", [?MODULE]),
+    State;
+notify(_Note,State) ->
+    State.
+
+%%%-----------------------------------------------------------------
+%%% Internal functions
+try_log(Args) ->
+    try apply(logger,log,Args)
+    catch C:R:S ->
+            ?LOG_INTERNAL(debug,[{?MODULE,log_failed},
+                                 {log,Args},
+                                 {reason,{C,R,S}}])
+    end.
diff --git a/lib/kernel/src/logger_server.erl b/lib/kernel/src/logger_server.erl
index b7735dbcf7..722246e82c 100644
--- a/lib/kernel/src/logger_server.erl
+++ b/lib/kernel/src/logger_server.erl
@@ -22,8 +22,7 @@
 -behaviour(gen_server).
 
 %% API
--export([start_link/0,
-         add_handler/3, remove_handler/1,
+-export([start_link/0, add_handler/3, remove_handler/1,
          add_filter/2, remove_filter/2,
          set_module_level/2, unset_module_level/0,
          unset_module_level/1, cache_module_level/1,
@@ -43,7 +42,7 @@
 -define(SERVER, logger).
 -define(LOGGER_SERVER_TAG, '$logger_cb_process').
 
--record(state, {tid, async_req, async_req_queue}).
+-record(state, {tid, async_req, async_req_queue, remote_logger}).
 
 %%%===================================================================
 %%% API
@@ -155,6 +154,8 @@ init([]) ->
     process_flag(trap_exit, true),
     put(?LOGGER_SERVER_TAG,true),
     Tid = logger_config:new(?LOGGER_TABLE),
+    %% Store initial proxy config. logger_proxy reads config from here at startup.
+    logger_config:create(Tid,proxy,logger_proxy:get_default_config()),
     PrimaryConfig = maps:merge(default_config(primary),
                               #{handlers=>[simple]}),
     logger_config:create(Tid,primary,PrimaryConfig),
@@ -221,6 +222,24 @@ handle_call({add_filter,Id,Filter}, _From,#state{tid=Tid}=State) ->
 handle_call({remove_filter,Id,FilterId}, _From, #state{tid=Tid}=State) ->
     Reply = do_remove_filter(Tid,Id,FilterId),
     {reply,Reply,State};
+handle_call({change_config,SetOrUpd,proxy,Config0},_From,#state{tid=Tid}=State) ->
+    Default =
+        case SetOrUpd of
+            set ->
+                logger_proxy:get_default_config();
+            update ->
+                {ok,OldConfig} = logger_config:get(Tid,proxy),
+                OldConfig
+        end,
+    Config = maps:merge(Default,Config0),
+    Reply =
+        case logger_olp:set_opts(logger_proxy,Config) of
+            ok ->
+                logger_config:set(Tid,proxy,Config);
+            Error ->
+                Error
+        end,
+    {reply,Reply,State};
 handle_call({change_config,SetOrUpd,primary,Config0}, _From,
             #state{tid=Tid}=State) ->
     {ok,#{handlers:=Handlers}=OldConfig} = logger_config:get(Tid,primary),
@@ -357,7 +376,7 @@ terminate(_Reason, _State) ->
 %%%===================================================================
 %%% Internal functions
 %%%===================================================================
-call(Request) ->
+call(Request) when is_tuple(Request) ->
     Action = element(1,Request),
     case get(?LOGGER_SERVER_TAG) of
         true when
@@ -369,6 +388,7 @@ call(Request) ->
             gen_server:call(?SERVER,Request,?DEFAULT_LOGGER_CALL_TIMEOUT)
     end.
 
+
 do_add_filter(Tid,Id,{FId,_} = Filter) ->
     case logger_config:get(Tid,Id) of
         {ok,Config} ->
@@ -413,11 +433,13 @@ default_config(Id,Module) ->
 sanity_check(Owner,Key,Value) ->
     sanity_check_1(Owner,[{Key,Value}]).
 
-sanity_check(HandlerId,Config) when is_map(Config) ->
-    sanity_check_1(HandlerId,maps:to_list(Config));
+sanity_check(Owner,Config) when is_map(Config) ->
+    sanity_check_1(Owner,maps:to_list(Config));
 sanity_check(_,Config) ->
     {error,{invalid_config,Config}}.
 
+sanity_check_1(proxy,_Config) ->
+    ok; % Details are checked by logger_olp:set_opts/2
 sanity_check_1(Owner,Config) when is_list(Config) ->
     try
         Type = get_type(Owner),
diff --git a/lib/kernel/src/logger_std_h.erl b/lib/kernel/src/logger_std_h.erl
index 63d1dbaba2..0669164bb6 100644
--- a/lib/kernel/src/logger_std_h.erl
+++ b/lib/kernel/src/logger_std_h.erl
@@ -26,7 +26,7 @@
 -include_lib("kernel/include/file.hrl").
 
 %% API
--export([info/1, filesync/1, reset/1]).
+-export([filesync/1]).
 
 %% logger_h_common callbacks
 -export([init/2, check_config/4, reset_state/2,
@@ -36,6 +36,8 @@
 -export([log/2, adding_handler/1, removing_handler/1, changing_config/3,
          filter_config/1]).
 
+-define(DEFAULT_CALL_TIMEOUT, 5000).
+
 %%%===================================================================
 %%% API
 %%%===================================================================
@@ -49,25 +51,6 @@
 filesync(Name) ->
     logger_h_common:filesync(?MODULE,Name).
 
-%%%-----------------------------------------------------------------
-%%%
--spec info(Name) -> Info | {error,Reason} when
-      Name :: atom(),
-      Info :: term(),
-      Reason :: handler_busy | {badarg,term()}.
-
-info(Name) ->
-    logger_h_common:info(?MODULE,Name).
-
-%%%-----------------------------------------------------------------
-%%%
--spec reset(Name) -> ok | {error,Reason} when
-      Name :: atom(),
-      Reason :: handler_busy | {badarg,term()}.
-
-reset(Name) ->
-    logger_h_common:reset(?MODULE,Name).
-
 %%%===================================================================
 %%% logger callbacks - just forward to logger_h_common
 %%%===================================================================
diff --git a/lib/kernel/src/logger_sup.erl b/lib/kernel/src/logger_sup.erl
index 3d6f482e20..9ea8558a16 100644
--- a/lib/kernel/src/logger_sup.erl
+++ b/lib/kernel/src/logger_sup.erl
@@ -50,7 +50,9 @@ init([]) ->
                 start => {logger_handler_watcher, start_link, []},
                 shutdown => brutal_kill},
 
-    {ok, {SupFlags, [Watcher]}}.
+    Proxy = logger_proxy:child_spec(),
+
+    {ok, {SupFlags, [Watcher,Proxy]}}.
 
 %%%===================================================================
 %%% Internal functions
diff --git a/lib/kernel/test/Makefile b/lib/kernel/test/Makefile
index 4a86265a4a..8a6ffe7e72 100644
--- a/lib/kernel/test/Makefile
+++ b/lib/kernel/test/Makefile
@@ -76,8 +76,11 @@ MODULES= \
 	logger_filters_SUITE \
 	logger_formatter_SUITE \
 	logger_legacy_SUITE \
+	logger_olp_SUITE \
+	logger_proxy_SUITE \
 	logger_simple_h_SUITE \
 	logger_std_h_SUITE \
+	logger_stress_SUITE \
 	logger_test_lib \
 	os_SUITE \
 	pg2_SUITE \
diff --git a/lib/kernel/test/kernel_bench.spec b/lib/kernel/test/kernel_bench.spec
index 4de133f21b..898ceb59e0 100644
--- a/lib/kernel/test/kernel_bench.spec
+++ b/lib/kernel/test/kernel_bench.spec
@@ -1,2 +1,3 @@
 {groups,"../kernel_test",zlib_SUITE,[bench]}.
 {groups,"../kernel_test",file_SUITE,[bench]}.
+{suites,"../kernel_test",[logger_stress_SUITE]}.
diff --git a/lib/kernel/test/logger.cover b/lib/kernel/test/logger.cover
index 960bc0abff..9691aa295e 100644
--- a/lib/kernel/test/logger.cover
+++ b/lib/kernel/test/logger.cover
@@ -4,9 +4,12 @@
             logger_backend,
             logger_config,
             logger_disk_log_h,
-            logger_h_common,
             logger_filters,
             logger_formatter,
+            logger_handler_watcher,
+            logger_h_common,
+            logger_olp,
+            logger_proxy,
             logger_server,
             logger_simple_h,
             logger_std_h,
diff --git a/lib/kernel/test/logger.spec b/lib/kernel/test/logger.spec
index 1ab90b3e93..3aec37951d 100644
--- a/lib/kernel/test/logger.spec
+++ b/lib/kernel/test/logger.spec
@@ -7,5 +7,7 @@
                            logger_filters_SUITE,
                            logger_formatter_SUITE,
                            logger_legacy_SUITE,
+                           logger_olp_SUITE,
+                           logger_proxy_SUITE,
                            logger_simple_h_SUITE,
                            logger_std_h_SUITE]}.
diff --git a/lib/kernel/test/logger_disk_log_h_SUITE.erl b/lib/kernel/test/logger_disk_log_h_SUITE.erl
index 87b8250781..9bbec42de8 100644
--- a/lib/kernel/test/logger_disk_log_h_SUITE.erl
+++ b/lib/kernel/test/logger_disk_log_h_SUITE.erl
@@ -24,6 +24,7 @@
 -include_lib("common_test/include/ct.hrl").
 -include_lib("kernel/include/logger.hrl").
 -include_lib("kernel/src/logger_internal.hrl").
+-include_lib("kernel/src/logger_olp.hrl").
 -include_lib("kernel/src/logger_h_common.hrl").
 -include_lib("stdlib/include/ms_transform.hrl").
 -include_lib("kernel/include/file.hrl").
@@ -97,7 +98,6 @@ all() ->
      formatter_fail,
      config_fail,
      bad_input,
-     info_and_reset,
      reconfig,
      sync,
      disk_log_full,
@@ -306,9 +306,9 @@ logging(cleanup, _Config) ->
 filter_config(_Config) ->
     ok = logger:add_handler(?MODULE,logger_disk_log_h,#{}),
     {ok,#{config:=HConfig}=Config} = logger:get_handler_config(?MODULE),
-    HConfig = maps:without([handler_pid,mode_tab],HConfig),
+    HConfig = maps:without([olp],HConfig),
 
-    FakeFullHConfig = HConfig#{handler_pid=>self(),mode_tab=>erlang:make_ref()},
+    FakeFullHConfig = HConfig#{olp=>{regname,self(),erlang:make_ref()}},
     #{config:=HConfig} =
         logger_disk_log_h:filter_config(Config#{config=>FakeFullHConfig}),
     ok.
@@ -351,9 +351,7 @@ errors(Config) ->
     %% Read-only fields may (accidentially) be included in the change,
     %% but it won't take effect
     {ok,C} = logger:get_handler_config(Name1),
-    ok = logger:set_handler_config(Name1,config,
-                                   #{handler_pid=>self(),
-                                     mode_tab=>erlang:make_ref()}),
+    ok = logger:set_handler_config(Name1,config,#{olp=>dummyvalue}),
     {ok,C} = logger:get_handler_config(Name1),
 
 
@@ -419,19 +417,16 @@ config_fail(_Config) ->
                              filter_default=>log,
                              formatter=>{?MODULE,self()}}),
 
-    {error,{handler_not_added,{invalid_config,logger_disk_log_h,
-                               {invalid_levels,#{drop_mode_qlen:=1}}}}} =
+    {error,{handler_not_added,{invalid_olp_levels,#{drop_mode_qlen:=1}}}} =
         logger:add_handler(?MODULE,logger_disk_log_h,
                            #{config => #{drop_mode_qlen=>1}}),
-    {error,{handler_not_added,{invalid_config,logger_disk_log_h,
-                               {invalid_levels,#{sync_mode_qlen:=43,
-                                                 drop_mode_qlen:=42}}}}} =
+    {error,{handler_not_added,{invalid_olp_levels,#{sync_mode_qlen:=43,
+                                                drop_mode_qlen:=42}}}} =
         logger:add_handler(?MODULE,logger_disk_log_h,
                            #{config => #{sync_mode_qlen=>43,
                                          drop_mode_qlen=>42}}),
-    {error,{handler_not_added,{invalid_config,logger_disk_log_h,
-                               {invalid_levels,#{drop_mode_qlen:=43,
-                                                 flush_qlen:=42}}}}} =
+    {error,{handler_not_added,{invalid_olp_levels,#{drop_mode_qlen:=43,
+                                                flush_qlen:=42}}}} =
         logger:add_handler(?MODULE,logger_disk_log_h,
                            #{config => #{drop_mode_qlen=>43,
                                          flush_qlen=>42}}),
@@ -445,7 +440,7 @@ config_fail(_Config) ->
                                      #{max_no_files=>2}),
     %% incorrect values of OP params
     {ok,#{config := HConfig}} = logger:get_handler_config(?MODULE),
-    {error,{invalid_config,logger_disk_log_h,{invalid_levels,_}}} =
+    {error,{invalid_olp_levels,_}} =
         logger:update_handler_config(?MODULE,config,
                                      HConfig#{sync_mode_qlen=>100,
                                               flush_qlen=>99}),
@@ -459,18 +454,7 @@ config_fail(cleanup,_Config) ->
 
 bad_input(_Config) ->
     {error,{badarg,{filesync,["BadType"]}}} =
-        logger_disk_log_h:filesync("BadType"),
-    {error,{badarg,{info,["BadType"]}}} = logger_disk_log_h:info("BadType"),
-    {error,{badarg,{reset,["BadType"]}}} = logger_disk_log_h:reset("BadType").
-
-info_and_reset(_Config) ->
-    ok = logger:add_handler(?MODULE,logger_disk_log_h,
-                            #{filter_default=>log,
-                              formatter=>{?MODULE,self()}}),
-    #{id := ?MODULE} = logger_disk_log_h:info(?MODULE),
-    ok = logger_disk_log_h:reset(?MODULE).
-info_and_reset(cleanup,_Config) ->
-    logger:remove_handler(?MODULE).
+        logger_disk_log_h:filesync("BadType").
 
 reconfig(Config) ->
     Dir = ?config(priv_dir,Config),
@@ -479,7 +463,7 @@ reconfig(Config) ->
                             #{filter_default=>log,
                               filters=>?DEFAULT_HANDLER_FILTERS([?MODULE]),
                               formatter=>{?MODULE,self()}}),
-    #{id := ?MODULE,
+    #{%id := ?MODULE,
       sync_mode_qlen := ?SYNC_MODE_QLEN,
       drop_mode_qlen := ?DROP_MODE_QLEN,
       flush_qlen := ?FLUSH_QLEN,
@@ -490,13 +474,14 @@ reconfig(Config) ->
       overload_kill_qlen := ?OVERLOAD_KILL_QLEN,
       overload_kill_mem_size := ?OVERLOAD_KILL_MEM_SIZE,
       overload_kill_restart_after := ?OVERLOAD_KILL_RESTART_AFTER,
-      filesync_repeat_interval := ?FILESYNC_REPEAT_INTERVAL,
-      handler_state :=
-          #{log_opts := #{type := ?DISK_LOG_TYPE,
-                          max_no_files := ?DISK_LOG_MAX_NO_FILES,
-                          max_no_bytes := ?DISK_LOG_MAX_NO_BYTES,
-                          file := DiskLogFile}}} =
-        logger_disk_log_h:info(?MODULE),
+      cb_state :=
+          #{handler_state :=
+                #{log_opts := #{type := ?DISK_LOG_TYPE,
+                                max_no_files := ?DISK_LOG_MAX_NO_FILES,
+                                max_no_bytes := ?DISK_LOG_MAX_NO_BYTES,
+                                file := DiskLogFile}},
+            filesync_repeat_interval := ?FILESYNC_REPEAT_INTERVAL}} =
+        logger_olp:info(h_proc_name()),
     {ok,#{config :=
               #{sync_mode_qlen := ?SYNC_MODE_QLEN,
                 drop_mode_qlen := ?DROP_MODE_QLEN,
@@ -527,7 +512,7 @@ reconfig(Config) ->
                          overload_kill_restart_after => infinity,
                          filesync_repeat_interval => no_repeat},
     ok = logger:set_handler_config(?MODULE, config, HConfig1),
-    #{id := ?MODULE,
+    #{%id := ?MODULE,
       sync_mode_qlen := 1,
       drop_mode_qlen := 2,
       flush_qlen := 3,
@@ -538,8 +523,8 @@ reconfig(Config) ->
       overload_kill_qlen := 100000,
       overload_kill_mem_size := 10000000,
       overload_kill_restart_after := infinity,
-      filesync_repeat_interval := no_repeat} =
-        logger_disk_log_h:info(?MODULE),
+      cb_state := #{filesync_repeat_interval := no_repeat}} =
+        logger_olp:info(h_proc_name()),
     {ok,#{config:=HConfig1}} = logger:get_handler_config(?MODULE),
 
     ok = logger:update_handler_config(?MODULE, config,
@@ -577,12 +562,13 @@ reconfig(Config) ->
                                     max_no_files => 1,
                                     max_no_bytes => 1024,
                                     file => File}}),
-    #{handler_state :=
-          #{log_opts := #{type := halt,
-                          max_no_files := 1,
-                          max_no_bytes := 1024,
-                          file := File}}} =
-        logger_disk_log_h:info(?MODULE),
+    #{cb_state :=
+          #{handler_state :=
+                #{log_opts := #{type := halt,
+                                max_no_files := 1,
+                                max_no_bytes := 1024,
+                                file := File}}}} =
+        logger_olp:info(h_proc_name()),
     {ok,#{config :=
               #{type := halt,
                 max_no_files := 1,
@@ -650,13 +636,8 @@ sync(Config) ->
     {ok,#{config := HConfig}} = logger:get_handler_config(?MODULE),
     HConfig1 = HConfig#{filesync_repeat_interval => no_repeat},
     ok = logger:update_handler_config(?MODULE, config, HConfig1),
-
     no_repeat = maps:get(filesync_repeat_interval,
-                         logger_disk_log_h:info(?MODULE)),
-    %% The following timer is to make sure the time from last log
-    %% ("first") to next ("second") is long enough, so the a flush is
-    %% triggered by the idle timeout between "fourth" and "fifth".
-    timer:sleep(?IDLE_DETECT_TIME_MSEC*2),
+                         maps:get(cb_state,logger_olp:info(h_proc_name()))),
 
     start_tracer([{logger_disk_log_h,disk_log_write,3},
                   {disk_log,sync,1}],
@@ -666,10 +647,10 @@ sync(Config) ->
                   {disk_log,sync}]),
 
     logger:notice("second", ?domain),
-    timer:sleep(?IDLE_DETECT_TIME_MSEC*2),
+    timer:sleep(?IDLE_DETECT_TIME*2),
     logger:notice("third", ?domain),
     %% wait for automatic disk_log_sync
-    check_tracer(?IDLE_DETECT_TIME_MSEC*2),
+    check_tracer(?IDLE_DETECT_TIME*2),
 
     try_read_file(Log, {ok,<<"first\nsecond\nthird\n">>}, 1000),
     
@@ -678,14 +659,15 @@ sync(Config) ->
     WaitT = 4500,
     OneSync = {logger_h_common,handle_cast,repeated_filesync},
     %% receive 1 repeated_filesync per sec
-    start_tracer([{logger_h_common,handle_cast,2}],
+    start_tracer([{{logger_h_common,handle_cast,2},
+                   [{[repeated_filesync,'_'],[],[{message,{caller}}]}]}],
                  [OneSync || _ <- lists:seq(1, trunc(WaitT/SyncInt))]),
 
     HConfig2 = HConfig#{filesync_repeat_interval => SyncInt},
     ok = logger:update_handler_config(?MODULE, config, HConfig2),
                       
     SyncInt = maps:get(filesync_repeat_interval,
-                       logger_disk_log_h:info(?MODULE)),
+                       maps:get(cb_state,logger_olp:info(h_proc_name()))),
     timer:sleep(WaitT),
     HConfig3 = HConfig#{filesync_repeat_interval => no_repeat},
     ok = logger:update_handler_config(?MODULE, config, HConfig3),
@@ -803,7 +785,7 @@ disk_log_full(cleanup, _Config) ->
     dbg:stop_clear(),
     logger:remove_handler(?MODULE).    
 
-disk_log_events(Config) ->
+disk_log_events(_Config) ->
     Node = node(),
     Log = ?MODULE,
     ok = logger:add_handler(?MODULE,
@@ -860,10 +842,12 @@ write_failure(Config) ->
     rpc:call(Node, ets, insert, [?TEST_HOOKS_TAB,{tester,self()}]),
     rpc:call(Node, ?MODULE, set_internal_log, [?MODULE,internal_log]),
     rpc:call(Node, ?MODULE, set_result, [disk_log_write,ok]),
-    HState = rpc:call(Node, logger_disk_log_h, info, [?STANDARD_HANDLER]),
-    ct:pal("LogOpts = ~p", [LogOpts = maps:get(log_opts,
-                                               maps:get(handler_state,HState))]),
-
+    HState = rpc:call(Node, logger_olp, info, [h_proc_name(?STANDARD_HANDLER)]),
+    LogOpts = maps:get(log_opts,
+                       maps:get(handler_state,
+                                maps:get(cb_state,HState))),
+    ct:pal("LogOpts = ~p", [LogOpts]),
+           
     %% ?check and ?check_no_log in this test only check for internal log events
     ok = log_on_remote_node(Node, "Logged1"),
     rpc:call(Node, logger_disk_log_h, filesync, [?STANDARD_HANDLER]),
@@ -914,15 +898,16 @@ sync_failure(Config) ->
     rpc:call(Node, ets, insert, [?TEST_HOOKS_TAB,{tester,self()}]),
     rpc:call(Node, ?MODULE, set_internal_log, [?MODULE,internal_log]),
     rpc:call(Node, ?MODULE, set_result, [disk_log_sync,ok]),
-    HState = rpc:call(Node, logger_disk_log_h, info, [?STANDARD_HANDLER]),
-    LogOpts = maps:get(log_opts, maps:get(handler_state,HState)),
+    HState = rpc:call(Node, logger_olp, info, [h_proc_name(?STANDARD_HANDLER)]),
+    LogOpts = maps:get(log_opts, maps:get(handler_state,
+                                          maps:get(cb_state,HState))),
     
     SyncInt = 500,
     ok = rpc:call(Node, logger, update_handler_config,
                   [?STANDARD_HANDLER, config,
                    #{filesync_repeat_interval => SyncInt}]),
-    Info = rpc:call(Node, logger_disk_log_h, info, [?STANDARD_HANDLER]),
-    SyncInt = maps:get(filesync_repeat_interval, Info),
+    Info = rpc:call(Node, logger_olp, info, [h_proc_name(?STANDARD_HANDLER)]),
+    SyncInt = maps:get(filesync_repeat_interval, maps:get(cb_state, Info)),
     
     ok = log_on_remote_node(Node, "Logged1"),
     ?check_no_log,
@@ -1198,7 +1183,7 @@ qlen_kill_new(Config) ->
     receive
         {'DOWN', MRef, _, _, Info} ->
            case Info of
-                {shutdown,{overloaded,?MODULE,QLen,Mem}} ->
+                {shutdown,{overloaded,QLen,Mem}} ->
                     ct:pal("Terminated with qlen = ~w, mem = ~w", [QLen,Mem]);
                 killed ->
                     ct:pal("Slow shutdown, handler process was killed!", [])
@@ -1208,7 +1193,7 @@ qlen_kill_new(Config) ->
             ok
     after
         5000 ->
-            Info = logger_disk_log_h:info(?MODULE),
+            Info = logger_olp:info(h_proc_name()),
             ct:pal("Handler state = ~p", [Info]),
             ct:fail("Handler not dead! It should not have survived this!")
     end.
@@ -1235,7 +1220,7 @@ mem_kill_new(Config) ->
     receive
         {'DOWN', MRef, _, _, Info} ->
             case Info of
-                {shutdown,{overloaded,?MODULE,QLen,Mem}} ->
+                {shutdown,{overloaded,QLen,Mem}} ->
                     ct:pal("Terminated with qlen = ~w, mem = ~w", [QLen,Mem]);
                 killed ->
                     ct:pal("Slow shutdown, handler process was killed!", [])
@@ -1245,7 +1230,7 @@ mem_kill_new(Config) ->
             ok
     after
         5000 ->
-            Info = logger_disk_log_h:info(?MODULE),
+            Info = logger_olp:info(h_proc_name()),
             ct:pal("Handler state = ~p", [Info]),
             ct:fail("Handler not dead! It should not have survived this!")
     end.
@@ -1271,7 +1256,7 @@ restart_after(Config) ->
             ok
     after
         5000 ->
-            Info1 = logger_std_h:info(?MODULE),
+            Info1 = logger_olp:info(h_proc_name()),
             ct:pal("Handler state = ~p", [Info1]),
             ct:fail("Handler not dead! It should not have survived this!")
     end,
@@ -1295,7 +1280,7 @@ restart_after(Config) ->
             ok
     after
         5000 ->
-            Info2 = logger_std_h:info(?MODULE),
+            Info2 = logger_olp:info(h_proc_name()),
             ct:pal("Handler state = ~p", [Info2]),
             ct:fail("Handler not dead! It should not have survived this!")
     end,
@@ -1316,11 +1301,15 @@ handler_requests_under_load(Config) ->
                                       flush_qlen => 2000,
                                       burst_limit_enable => false}},
     ok = logger:update_handler_config(?MODULE, NewHConfig),
-    Pid = spawn_link(fun() -> send_requests(?MODULE, 1, [{filesync,[]},
-                                                         {info,[]},
-                                                         {reset,[]},
-                                                         {change_config,[]}])
-                     end),
+    Pid = spawn_link(
+            fun() -> send_requests(1,[{logger_disk_log_h,filesync,[?MODULE],[]},
+                                      {logger_olp,info,[h_proc_name()],[]},
+                                      {logger_olp,reset,[h_proc_name()],[]},
+                                      {logger,update_handler_config,
+                                       [?MODULE, config,
+                                        #{overload_kill_enable => false}],
+                                       []}])
+            end),
     Procs = 100,
     Sent = Procs * send_burst({n,5000}, {spawn,Procs,10}, {chars,79}, notice),
     Pid ! {self(),finish},
@@ -1332,29 +1321,22 @@ handler_requests_under_load(Config) ->
                         [E || E <- Res,
                               is_tuple(E) andalso (element(1,E) == error)]
                 end,
-    Errors = [{Req,FindError(Res)} || {Req,Res} <- ReqResult],
-    NoOfReqs = lists:foldl(fun({_,Res}, N) -> N + length(Res) end, 0, ReqResult),
+    Errors = [{Func,FindError(Res)} || {_,Func,_,Res} <- ReqResult],
+    NoOfReqs = lists:foldl(fun({_,_,_,Res}, N) -> N + length(Res) end,
+                           0, ReqResult),
     ct:pal("~w requests made. Errors: ~n~p", [NoOfReqs,Errors]),
     ok = file_delete(Log).
 handler_requests_under_load(cleanup, _Config) ->
     ok = stop_handler(?MODULE).
 
-send_requests(HName, TO, Reqs = [{Req,Res}|Rs]) ->
+send_requests(TO, Reqs = [{Mod,Func,Args,Res}|Rs]) ->
     receive
         {From,finish} ->
             From ! {self(),Reqs}
     after
         TO ->
-            Result =
-                case Req of
-                    change_config ->
-                        logger:update_handler_config(HName, logger_disk_log_h,
-                                                     #{overload_kill_enable =>
-                                                           false});
-                    Func ->
-                        logger_disk_log_h:Func(HName)
-                end,
-            send_requests(HName, TO, Rs ++ [{Req,[Result|Res]}])
+            Result = apply(Mod,Func,Args),
+            send_requests(TO, Rs ++ [{Mod,Func,Args,[Result|Res]}])
     end.
 
 %%%-----------------------------------------------------------------
@@ -1472,15 +1454,6 @@ format(Msg,Tag) ->
     erlang:display(Error),
     exit(Error).
 
-remove(Handler, LogName) ->
-    logger_disk_log_h:remove(Handler, LogName),
-    HState = #{log_names := Logs} = logger_disk_log_h:info(),
-    false = maps:is_key(LogName, HState),
-    false = lists:member(LogName, Logs),
-    false = logger_config:exist(?LOGGER_TABLE, LogName),
-    {error,no_such_log} = disk_log:info(LogName),
-    ok.
-
 start_and_add(Name, Config, LogOpts) ->
     HConfig = maps:get(config, Config, #{}),
     HConfig1 = maps:merge(HConfig, LogOpts),
@@ -1607,7 +1580,9 @@ start_tracer(Trace,Expected) ->
     ok.
 
 tpl([{M,F,A}|Trace]) ->
-    {ok,Match} = dbg:tpl(M,F,A,c),
+    tpl([{{M,F,A},c}|Trace]);
+tpl([{{M,F,A},MS}|Trace]) ->
+    {ok,Match} = dbg:tpl(M,F,A,MS),
     case lists:keyfind(matched,1,Match) of
         {_,_,1} ->
             ok;
diff --git a/lib/kernel/test/logger_env_var_SUITE.erl b/lib/kernel/test/logger_env_var_SUITE.erl
index e8d1a313dc..9d2ad11be8 100644
--- a/lib/kernel/test/logger_env_var_SUITE.erl
+++ b/lib/kernel/test/logger_env_var_SUITE.erl
@@ -59,7 +59,8 @@ groups() ->
                  logger_undefined,
                  logger_many_handlers_default_first,
                  logger_many_handlers_default_last,
-                 logger_many_handlers_default_last_broken_filter
+                 logger_many_handlers_default_last_broken_filter,
+                 logger_proxy
                 ]},
      {bad,[],[bad_error_logger,
               bad_level,
@@ -541,6 +542,19 @@ logger_many_handlers(Config, Env, LogErr, LogInfo, NumProgress) ->
 
     ok.
 
+logger_proxy(Config) ->
+    %% assume current node runs with default settings
+    DefOpts = logger_olp:get_opts(logger_proxy),
+    {ok,_,Node} = setup(Config,
+                        [{logger,[{proxy,#{sync_mode_qlen=>0,
+                                           drop_mode_qlen=>2}}]}]),
+    Expected = DefOpts#{sync_mode_qlen:=0,
+                        drop_mode_qlen:=2},
+    Expected = rpc:call(Node,logger_olp,get_opts,[logger_proxy]),
+    Expected = rpc:call(Node,logger,get_proxy_config,[]),
+
+    ok.
+
 sasl_compatible_false(Config) ->
     Log = file(Config,?FUNCTION_NAME),
     {ok,_,Node} = setup(Config,
diff --git a/lib/kernel/test/logger_olp_SUITE.erl b/lib/kernel/test/logger_olp_SUITE.erl
new file mode 100644
index 0000000000..ea3eec89f5
--- /dev/null
+++ b/lib/kernel/test/logger_olp_SUITE.erl
@@ -0,0 +1,90 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2018. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+-module(logger_olp_SUITE).
+
+-compile(export_all).
+
+-include_lib("kernel/src/logger_olp.hrl").
+
+suite() ->
+    [{timetrap,{seconds,30}}].
+
+init_per_suite(Config) ->
+    Config.
+
+end_per_suite(_Config) ->
+    ok.
+
+init_per_group(_Group, Config) ->
+    Config.
+
+end_per_group(_Group, _Config) ->
+    ok.
+
+init_per_testcase(_TestCase, Config) ->
+    Config.
+
+end_per_testcase(Case, Config) ->
+    try apply(?MODULE,Case,[cleanup,Config])
+    catch error:undef -> ok
+    end,
+    ok.
+
+groups() ->
+    [].
+
+all() -> 
+    [idle_timer].
+
+%%%-----------------------------------------------------------------
+%%% Test cases
+idle_timer(_Config) ->
+    {ok,_Pid,Olp} = logger_olp:start_link(?MODULE,?MODULE,self(),#{}),
+    [logger_olp:load(Olp,{msg,N}) || N<-lists:seq(1,3)],
+    timer:sleep(?IDLE_DETECT_TIME*2),
+    [{load,{msg,1}},
+     {load,{msg,2}},
+     {load,{msg,3}},
+     {notify,idle}] = test_server:messages_get(),
+    logger_olp:cast(Olp,hello),
+    timer:sleep(?IDLE_DETECT_TIME*2),
+    [{cast,hello}] = test_server:messages_get(),
+    ok.
+idle_timer(cleanup,_Config) ->
+    unlink(whereis(?MODULE)),
+    logger_olp:stop(?MODULE),
+    ok.
+
+%%%-----------------------------------------------------------------
+%%% Olp callbacks
+init(P) ->
+    {ok,P}.
+
+handle_load(M,P) ->
+    P ! {load,M},
+    P.
+
+handle_cast(M,P) ->
+    P ! {cast,M},
+    {noreply,P}.
+
+notify(N,P) ->
+    P ! {notify,N},
+    P.
diff --git a/lib/kernel/test/logger_proxy_SUITE.erl b/lib/kernel/test/logger_proxy_SUITE.erl
new file mode 100644
index 0000000000..777531e4ed
--- /dev/null
+++ b/lib/kernel/test/logger_proxy_SUITE.erl
@@ -0,0 +1,274 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2018. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+-module(logger_proxy_SUITE).
+
+-compile(export_all).
+
+%% -include_lib("common_test/include/ct.hrl").
+%% -include_lib("kernel/include/logger.hrl").
+%% -include_lib("kernel/src/logger_internal.hrl").
+
+%% -define(str,"Log from "++atom_to_list(?FUNCTION_NAME)++
+%%             ":"++integer_to_list(?LINE)).
+%% -define(map_rep,#{function=>?FUNCTION_NAME, line=>?LINE}).
+%% -define(keyval_rep,[{function,?FUNCTION_NAME}, {line,?LINE}]).
+
+%% -define(MY_LOC(N),#{mfa=>{?MODULE,?FUNCTION_NAME,?FUNCTION_ARITY},
+%%                     file=>?FILE, line=>?LINE-N}).
+
+%% -define(TRY(X), my_try(fun() -> X end)).
+
+
+-define(HNAME,list_to_atom(lists:concat([?MODULE,"_",?FUNCTION_NAME]))).
+-define(LOC,#{mfa=>{?MODULE,?FUNCTION_NAME,?FUNCTION_ARITY},line=>?LINE}).
+-define(ENSURE_TIME,5000).
+
+suite() ->
+    [{timetrap,{seconds,30}},
+     {ct_hooks,[logger_test_lib]}].
+
+init_per_suite(Config) ->
+    Config.
+
+end_per_suite(_Config) ->
+    ok.
+
+init_per_group(_Group, Config) ->
+    Config.
+
+end_per_group(_Group, _Config) ->
+    ok.
+
+init_per_testcase(_TestCase, Config) ->
+    Config.
+
+end_per_testcase(Case, Config) ->
+    try apply(?MODULE,Case,[cleanup,Config])
+    catch error:undef -> ok
+    end,
+    ok.
+
+groups() ->
+    [].
+
+all() -> 
+    [basic,
+     emulator,
+     remote,
+     remote_emulator,
+     config,
+     restart_after,
+     terminate].
+
+%%%-----------------------------------------------------------------
+%%% Test cases
+basic(_Config) ->
+    ok = logger:add_handler(?HNAME,?MODULE,#{config=>self()}),
+    logger_proxy ! {log,notice,"Log from: ~p; ~p",[?FUNCTION_NAME,?LINE],L1=?LOC},
+    ok = ensure(L1),
+    logger_proxy ! {log,notice,[{test_case,?FUNCTION_NAME},{line,?LINE}],L2=?LOC},
+    ok = ensure(L2),
+    logger_proxy:log({remote,node(),{log,notice,
+                                     "Log from: ~p; ~p",
+                                     [?FUNCTION_NAME,?LINE],
+                                     L3=?LOC}}),
+    ok = ensure(L3),
+    logger_proxy:log({remote,node(),{log,notice,
+                                     [{test_case,?FUNCTION_NAME},
+                                      {line,?LINE}],
+                                     L4=?LOC}}),
+    ok = ensure(L4),
+    ok.
+basic(cleanup,_Config) ->
+    ok = logger:remove_handler(?HNAME).
+
+emulator(_Config) ->
+    ok = logger:add_handler(?HNAME,?MODULE,#{config=>self()}),
+    Pid = spawn(fun() -> erlang:error(some_reason) end),
+    ok = ensure(#{pid=>Pid}),
+    ok.
+emulator(cleanup,_Config) ->
+    ok = logger:remove_handler(?HNAME).
+
+remote(Config) ->
+    {ok,_,Node} = logger_test_lib:setup(Config,[{logger,[{proxy,#{}}]}]),
+    ok = logger:add_handler(?HNAME,?MODULE,#{config=>self()}),
+    L1 = ?LOC, spawn(Node,fun() -> logger:notice("Log from ~p; ~p",[?FUNCTION_NAME,?LINE],L1) end),
+    ok = ensure(L1),
+    L2 = ?LOC, spawn(Node,fun() -> logger:notice([{test_case,?FUNCTION_NAME},{line,?LINE}],L2) end),
+    ok = ensure(L2),
+    ok.
+remote(cleanup,_Config) ->
+    ok = logger:remove_handler(?HNAME).
+
+remote_emulator(Config) ->
+    {ok,_,Node} = logger_test_lib:setup(Config,[{logger,[{proxy,#{}}]}]),
+    ok = logger:add_handler(?HNAME,?MODULE,#{config=>self()}),
+    Pid = spawn(Node,fun() -> erlang:error(some_reason) end),
+    ok = ensure(#{pid=>Pid}),
+    ok.
+remote_emulator(cleanup,_Config) ->
+    ok = logger:remove_handler(?HNAME).
+
+config(_Config) ->
+    C1 = #{sync_mode_qlen:=SQ,
+           drop_mode_qlen:=DQ} = logger:get_proxy_config(),
+    C1 = logger_olp:get_opts(logger_proxy),
+
+    %% Update the existing config with these two values
+    SQ1 = SQ+1,
+    DQ1 = DQ+1,
+    ok = logger:update_proxy_config(#{sync_mode_qlen=>SQ1,
+                                      drop_mode_qlen=>DQ1}),
+    C2 = logger:get_proxy_config(), % reads from ets table
+    C2 = logger_olp:get_opts(logger_proxy), % ensure consistency with process opts
+    C2 = C1#{sync_mode_qlen:=SQ1,
+             drop_mode_qlen:=DQ1},
+
+    %% Update the existing again with only one value
+    SQ2 = SQ+2,
+    ok = logger:update_proxy_config(#{sync_mode_qlen=>SQ2}),
+    C3 = logger:get_proxy_config(),
+    C3 = logger_olp:get_opts(logger_proxy),
+    C3 = C2#{sync_mode_qlen:=SQ2},
+
+    %% Set the config, i.e. merge with defaults
+    ok = logger:set_proxy_config(#{sync_mode_qlen=>SQ1}),
+    C4 = logger:get_proxy_config(),
+    C4 = logger_olp:get_opts(logger_proxy),
+    C4 = C1#{sync_mode_qlen:=SQ1},
+
+    %% Reset to default
+    ok = logger:set_proxy_config(#{}),
+    C5 = logger:get_proxy_config(),
+    C5 = logger_olp:get_opts(logger_proxy),
+    C5 = logger_proxy:get_default_config(),
+
+    %% Errors
+    {error,{invalid_olp_config,_}} =
+        logger:set_proxy_config(#{faulty_key=>1}),
+    {error,{invalid_olp_config,_}} =
+        logger:set_proxy_config(#{sync_mode_qlen=>infinity}),
+    {error,{invalid_config,[]}} = logger:set_proxy_config([]),
+
+    {error,{invalid_olp_config,_}} =
+        logger:update_proxy_config(#{faulty_key=>1}),
+    {error,{invalid_olp_config,_}} =
+        logger:update_proxy_config(#{sync_mode_qlen=>infinity}),
+    {error,{invalid_config,[]}} = logger:update_proxy_config([]),
+
+    C5 = logger:get_proxy_config(),
+    C5 = logger_olp:get_opts(logger_proxy),
+
+    ok.
+config(cleanup,_Config) ->
+    _ = logger:set_logger_proxy(logger_proxy:get_default_config()),
+    ok.
+
+restart_after(_Config) ->
+    Restart = 3000,
+    ok = logger:update_proxy_config(#{overload_kill_enable => true,
+                                      overload_kill_qlen => 10,
+                                      overload_kill_restart_after => Restart}),
+    Proxy = whereis(logger_proxy),
+    Proxy = erlang:system_info(system_logger),
+    ProxyConfig = logger:get_proxy_config(),
+    ProxyConfig = logger_olp:get_opts(logger_proxy),
+
+    Ref = erlang:monitor(process,Proxy),
+    spawn(fun() ->
+                  [logger_proxy ! {log,debug,
+                                   [{test_case,?FUNCTION_NAME},
+                                    {line,?LINE}],
+                                   ?LOC} || _ <- lists:seq(1,100)]
+          end),
+    receive
+        {'DOWN',Ref,_,_,_Reason} ->
+            undefined = erlang:system_info(system_logger),
+            timer:sleep(Restart),
+            poll_restarted(10)
+    after 5000 ->
+            ct:fail(proxy_not_terminated)
+    end,
+
+    Proxy1 = whereis(logger_proxy),
+    Proxy1 = erlang:system_info(system_logger),
+    ProxyConfig = logger:get_proxy_config(),
+    ProxyConfig = logger_olp:get_opts(logger_proxy),
+
+    ok.
+restart_after(cleanup,_Config) ->
+    _ = logger:set_logger_proxy(logger_proxy:get_default_config()),
+    ok.
+
+%% Test that system_logger flag is set to logger process if
+%% logger_proxy terminates for other reason than overloaded.
+terminate(_Config) ->
+    Logger = whereis(logger),
+    Proxy = whereis(logger_proxy),
+    Proxy = erlang:system_info(system_logger),
+    ProxyConfig = logger:get_proxy_config(),
+    ProxyConfig = logger_olp:get_opts(logger_proxy),
+
+    Ref = erlang:monitor(process,Proxy),
+    ok = logger_olp:stop(Proxy),
+    receive
+        {'DOWN',Ref,_,_,_Reason} ->
+            Logger = erlang:system_info(system_logger),
+            logger_proxy:restart(),
+            poll_restarted(10)
+    after 5000 ->
+            ct:fail(proxy_not_terminated)
+    end,
+
+    Proxy1 = whereis(logger_proxy),
+    Proxy1 = erlang:system_info(system_logger),
+    ProxyConfig = logger:get_proxy_config(),
+    ProxyConfig = logger_olp:get_opts(logger_proxy),
+
+    ok.
+
+%%%-----------------------------------------------------------------
+%%% Internal functions
+
+poll_restarted(0) ->
+    ct:fail(proxy_not_restarted);
+poll_restarted(N) ->
+    timer:sleep(1000),
+    case whereis(logger_proxy) of
+        undefined ->
+            poll_restarted(N-1);
+        _Pid ->
+            ok
+    end.
+
+%% Logger handler callback
+log(#{meta:=Meta},#{config:=Pid}) ->
+    Pid ! {logged,Meta}.
+
+%% Check that the log from the logger callback function log/2 is received
+ensure(Match) ->
+    receive {logged,Meta} ->
+            case maps:with(maps:keys(Match),Meta) of
+                Match -> ok;
+                _NoMatch -> {error,Match,Meta,test_server:messages_get()}
+            end
+    after ?ENSURE_TIME -> {error,Match,test_server:messages_get()}
+    end.
diff --git a/lib/kernel/test/logger_std_h_SUITE.erl b/lib/kernel/test/logger_std_h_SUITE.erl
index eb17a6d857..484d914ec3 100644
--- a/lib/kernel/test/logger_std_h_SUITE.erl
+++ b/lib/kernel/test/logger_std_h_SUITE.erl
@@ -25,10 +25,15 @@
 -include_lib("kernel/include/logger.hrl").
 -include_lib("kernel/src/logger_internal.hrl").
 -include_lib("kernel/src/logger_h_common.hrl").
+-include_lib("kernel/src/logger_olp.hrl").
 -include_lib("stdlib/include/ms_transform.hrl").
 -include_lib("kernel/include/file.hrl").
 
--define(check_no_log, [] = test_server:messages_get()).
+-define(check_no_log,
+        begin
+            timer:sleep(?IDLE_DETECT_TIME*2),
+            [] = test_server:messages_get()
+        end).
 -define(check(Expected),
         receive
             {log,Expected} ->
@@ -115,7 +120,6 @@ all() ->
      crash_std_h_to_file,
      crash_std_h_to_disk_log,
      bad_input,
-     info_and_reset,
      reconfig,
      file_opts,
      sync,
@@ -209,9 +213,9 @@ default_formatter(_Config) ->
 filter_config(_Config) ->
     ok = logger:add_handler(?MODULE,logger_std_h,#{}),
     {ok,#{config:=HConfig}=Config} = logger:get_handler_config(?MODULE),
-    HConfig = maps:without([handler_pid,mode_tab],HConfig),
+    HConfig = maps:without([olp],HConfig),
 
-    FakeFullHConfig = HConfig#{handler_pid=>self(),mode_tab=>erlang:make_ref()},
+    FakeFullHConfig = HConfig#{olp=>{regname,self(),erlang:make_ref()}},
     #{config:=HConfig} =
         logger_std_h:filter_config(Config#{config=>FakeFullHConfig}),
     ok.
@@ -246,13 +250,13 @@ errors(Config) ->
         _ ->
             NoDir = lists:concat(["/",?MODULE,"_dir"]),
             {error,
-             {handler_not_added,{{open_failed,NoDir,eacces},_}}} =
+             {handler_not_added,{open_failed,NoDir,eacces}}} =
                 logger:add_handler(myh2,logger_std_h,
                                    #{config=>#{type=>{file,NoDir}}})
     end,
 
     {error,
-     {handler_not_added,{{open_failed,Log,_},_}}} =
+     {handler_not_added,{open_failed,Log,_}}} =
         logger:add_handler(myh3,logger_std_h,
                            #{config=>#{type=>{file,Log,[bad_file_opt]}}}),
 
@@ -320,19 +324,16 @@ config_fail(_Config) ->
                            #{config => #{restart_type => bad},
                              filter_default=>log,
                              formatter=>{?MODULE,self()}}),
-    {error,{handler_not_added,{invalid_config,logger_std_h,
-                               {invalid_levels,#{drop_mode_qlen:=1}}}}} =
+    {error,{handler_not_added,{invalid_olp_levels,#{drop_mode_qlen:=1}}}} =
         logger:add_handler(?MODULE,logger_std_h,
                            #{config => #{drop_mode_qlen=>1}}),
-    {error,{handler_not_added,{invalid_config,logger_std_h,
-                               {invalid_levels,#{sync_mode_qlen:=43,
-                                                 drop_mode_qlen:=42}}}}} =
+    {error,{handler_not_added,{invalid_olp_levels,#{sync_mode_qlen:=43,
+                                                    drop_mode_qlen:=42}}}} =
         logger:add_handler(?MODULE,logger_std_h,
                            #{config => #{sync_mode_qlen=>43,
                                          drop_mode_qlen=>42}}),
-    {error,{handler_not_added,{invalid_config,logger_std_h,
-                               {invalid_levels,#{drop_mode_qlen:=43,
-                                                 flush_qlen:=42}}}}} =
+    {error,{handler_not_added,{invalid_olp_levels,#{drop_mode_qlen:=43,
+                                                    flush_qlen:=42}}}} =
         logger:add_handler(?MODULE,logger_std_h,
                            #{config => #{drop_mode_qlen=>43,
                                          flush_qlen=>42}}),
@@ -344,7 +345,7 @@ config_fail(_Config) ->
         logger:set_handler_config(?MODULE,config,
                                   #{type=>{file,"file"}}),
 
-    {error,{invalid_config,logger_std_h,{invalid_levels,_}}} =
+    {error,{invalid_olp_levels,_}} =
         logger:set_handler_config(?MODULE,config,
                                   #{sync_mode_qlen=>100,
                                     flush_qlen=>99}),
@@ -355,9 +356,7 @@ config_fail(_Config) ->
     %% Read-only fields may (accidentially) be included in the change,
     %% but it won't take effect
     {ok,C} = logger:get_handler_config(?MODULE),
-    ok = logger:set_handler_config(?MODULE,config,
-                                   #{handler_pid=>self(),
-                                     mode_tab=>erlang:make_ref()}),
+    ok = logger:set_handler_config(?MODULE,config,#{olp=>dummyvalue}),
     {ok,C} = logger:get_handler_config(?MODULE),
 
     ok.
@@ -425,10 +424,13 @@ crash_std_h(Config,Func,Var,Type,Log) ->
 %% logger would send the log event to the logger process here instead
 %% of logging it itself.
 log_on_remote_node(Node,Msg) ->
+    Pid = self(),
     _ = spawn_link(Node,
                    fun() -> erlang:group_leader(whereis(user),self()),
-                            logger:notice(Msg)
+                            logger:notice(Msg),
+                            Pid ! done
                    end),
+    receive done -> ok end,
     ok.
 
 
@@ -456,14 +458,7 @@ sync_and_read(Node,file,Log) ->
     end.
 
 bad_input(_Config) ->
-    {error,{badarg,{filesync,["BadType"]}}} = logger_std_h:filesync("BadType"),
-    {error,{badarg,{info,["BadType"]}}} = logger_std_h:info("BadType"),
-    {error,{badarg,{reset,["BadType"]}}} = logger_std_h:reset("BadType").
-
-
-info_and_reset(_Config) ->
-    #{id := ?STANDARD_HANDLER} = logger_std_h:info(?STANDARD_HANDLER),
-    ok = logger_std_h:reset(?STANDARD_HANDLER).
+    {error,{badarg,{filesync,["BadType"]}}} = logger_std_h:filesync("BadType").
 
 reconfig(Config) ->
     Dir = ?config(priv_dir,Config),
@@ -473,9 +468,10 @@ reconfig(Config) ->
                               filter_default=>log,
                               filters=>?DEFAULT_HANDLER_FILTERS([?MODULE]),
                               formatter=>{?MODULE,self()}}),
-    #{id := ?MODULE,
-      handler_state := #{type := standard_io,
-                         file_ctrl_pid := FileCtrlPid},
+    #{%id := ?MODULE,
+      cb_state:=#{handler_state := #{type := standard_io,
+                                     file_ctrl_pid := FileCtrlPid},
+                  filesync_repeat_interval := no_repeat},
       sync_mode_qlen := ?SYNC_MODE_QLEN,
       drop_mode_qlen := ?DROP_MODE_QLEN,
       flush_qlen := ?FLUSH_QLEN,
@@ -485,9 +481,8 @@ reconfig(Config) ->
       overload_kill_enable := ?OVERLOAD_KILL_ENABLE,
       overload_kill_qlen := ?OVERLOAD_KILL_QLEN,
       overload_kill_mem_size := ?OVERLOAD_KILL_MEM_SIZE,
-      overload_kill_restart_after := ?OVERLOAD_KILL_RESTART_AFTER,
-      filesync_repeat_interval := no_repeat} = DefaultInfo =
-        logger_std_h:info(?MODULE),
+      overload_kill_restart_after := ?OVERLOAD_KILL_RESTART_AFTER} =
+        logger_olp:info(h_proc_name()),
 
     {ok,
      #{config:=
@@ -518,9 +513,10 @@ reconfig(Config) ->
                                      overload_kill_mem_size => 10000000,
                                      overload_kill_restart_after => infinity,
                                      filesync_repeat_interval => 5000}),
-    #{id := ?MODULE,
-      handler_state := #{type := standard_io,
-                         file_ctrl_pid := FileCtrlPid},
+    #{%id := ?MODULE,
+      cb_state := #{handler_state := #{type := standard_io,
+                                       file_ctrl_pid := FileCtrlPid},
+                    filesync_repeat_interval := no_repeat},
       sync_mode_qlen := 1,
       drop_mode_qlen := 2,
       flush_qlen := 3,
@@ -530,8 +526,7 @@ reconfig(Config) ->
       overload_kill_enable := true,
       overload_kill_qlen := 100000,
       overload_kill_mem_size := 10000000,
-      overload_kill_restart_after := infinity,
-      filesync_repeat_interval := no_repeat} = Info = logger_std_h:info(?MODULE),
+      overload_kill_restart_after := infinity} = logger_olp:info(h_proc_name()),
 
     {ok,#{config :=
               #{type := standard_io,
@@ -613,7 +608,7 @@ file_opts(Config) ->
     Log = filename:join(Dir, lists:concat([?FUNCTION_NAME,".log"])),
     BadFileOpts = [raw],
     BadType = {file,Log,BadFileOpts},
-    {error,{handler_not_added,{{open_failed,Log,enoent},_}}} =
+    {error,{handler_not_added,{open_failed,Log,enoent}}} =
         logger:add_handler(?MODULE, logger_std_h,
                            #{config => #{type => BadType}}),
 
@@ -626,7 +621,9 @@ file_opts(Config) ->
                               filters=>?DEFAULT_HANDLER_FILTERS([?MODULE]),
                               formatter=>{?MODULE,self()}}),
 
-    #{handler_state := #{type := OkType}} = logger_std_h:info(?MODULE),
+    #{cb_state := #{handler_state := #{type := OkType}}} =
+        logger_olp:info(h_proc_name()),
+    {ok,#{config := #{type := OkType}}} = logger:get_handler_config(?MODULE),
     logger:notice(M1=?msg,?domain),
     ?check(M1),
     B1 = ?bin(M1),
@@ -675,11 +672,8 @@ sync(Config) ->
     %% a filesync is still performed when handler goes idle
     ok = logger:update_handler_config(?MODULE, config,
                                       #{filesync_repeat_interval => no_repeat}),
-    no_repeat = maps:get(filesync_repeat_interval, logger_std_h:info(?MODULE)),
-    %% The following timer is to make sure the time from last log
-    %% ("second") to next ("third") is long enough, so the a flush is
-    %% triggered by the idle timeout between "thrid" and "fourth".
-    timer:sleep(?IDLE_DETECT_TIME_MSEC*2),
+    no_repeat = maps:get(filesync_repeat_interval,
+                         maps:get(cb_state, logger_olp:info(h_proc_name()))),
     start_tracer([{logger_std_h, write_to_dev, 5},
                   {file, datasync, 1}],
                  [{logger_std_h, write_to_dev, <<"third\n">>},
@@ -688,22 +682,24 @@ sync(Config) ->
                   {file,datasync}]),
     logger:notice("third", ?domain),
     %% wait for automatic filesync
-    timer:sleep(?IDLE_DETECT_TIME_MSEC*2),
+    timer:sleep(?IDLE_DETECT_TIME*2),
     logger:notice("fourth", ?domain),
     %% wait for automatic filesync
-    check_tracer(?IDLE_DETECT_TIME_MSEC*2),
+    check_tracer(?IDLE_DETECT_TIME*2),
 
     %% switch repeated filesync on and verify that the looping works
     SyncInt = 1000,
     WaitT = 4500,
     OneSync = {logger_h_common,handle_cast,repeated_filesync},
     %% receive 1 repeated_filesync per sec
-    start_tracer([{logger_h_common,handle_cast,2}],
+    start_tracer([{{logger_h_common,handle_cast,2},
+                   [{[repeated_filesync,'_'],[],[]}]}],
                  [OneSync || _ <- lists:seq(1, trunc(WaitT/SyncInt))]),
 
     ok = logger:update_handler_config(?MODULE, config,
                                       #{filesync_repeat_interval => SyncInt}),
-    SyncInt = maps:get(filesync_repeat_interval, logger_std_h:info(?MODULE)),
+    SyncInt = maps:get(filesync_repeat_interval,
+                       maps:get(cb_state,logger_olp:info(h_proc_name()))),
     timer:sleep(WaitT),
     ok = logger:update_handler_config(?MODULE, config,
                                       #{filesync_repeat_interval => no_repeat}),
@@ -764,8 +760,6 @@ sync_failure(Config) ->
     ok = rpc:call(Node, logger, update_handler_config,
                   [?STANDARD_HANDLER, config,
                    #{filesync_repeat_interval => SyncInt}]),
-    Info = rpc:call(Node, logger_std_h, info, [?STANDARD_HANDLER]),
-    SyncInt = maps:get(filesync_repeat_interval, Info),
     
     ok = log_on_remote_node(Node, "Logged1"),
     ?check_no_log,
@@ -1095,7 +1089,7 @@ qlen_kill_new(Config) ->
     receive
         {'DOWN', MRef, _, _, Info} ->
            case Info of
-                {shutdown,{overloaded,?MODULE,QLen,Mem}} ->
+                {shutdown,{overloaded,QLen,Mem}} ->
                     ct:pal("Terminated with qlen = ~w, mem = ~w", [QLen,Mem]);
                 killed ->
                     ct:pal("Slow shutdown, handler process was killed!", [])
@@ -1105,7 +1099,7 @@ qlen_kill_new(Config) ->
             ok
     after
         5000 ->
-            Info = logger_std_h:info(?MODULE),
+            Info = logger_olp:info(h_proc_name()),
             ct:pal("Handler state = ~p", [Info]),
             ct:fail("Handler not dead! It should not have survived this!")
     end.
@@ -1146,7 +1140,7 @@ mem_kill_new(Config) ->
     receive
         {'DOWN', MRef, _, _, Info} ->
             case Info of
-                {shutdown,{overloaded,?MODULE,QLen,Mem}} ->
+                {shutdown,{overloaded,QLen,Mem}} ->
                     ct:pal("Terminated with qlen = ~w, mem = ~w", [QLen,Mem]);
                 killed ->
                     ct:pal("Slow shutdown, handler process was killed!", [])
@@ -1156,7 +1150,7 @@ mem_kill_new(Config) ->
             ok
     after
         5000 ->
-            Info = logger_std_h:info(?MODULE),
+            Info = logger_olp:info(h_proc_name()),
             ct:pal("Handler state = ~p", [Info]),
             ct:fail("Handler not dead! It should not have survived this!")
     end.
@@ -1187,7 +1181,7 @@ restart_after(Config) ->
             ok
     after
         5000 ->
-            Info1 = logger_std_h:info(?MODULE),
+            Info1 = logger_olp:info(h_proc_name()),
             ct:pal("Handler state = ~p", [Info1]),
             ct:fail("Handler not dead! It should not have survived this!")
     end,
@@ -1212,7 +1206,7 @@ restart_after(Config) ->
             ok
     after
         5000 ->
-            Info2 = logger_std_h:info(?MODULE),
+            Info2 = logger_olp:info(h_proc_name()),
             ct:pal("Handler state = ~p", [Info2]),
             ct:fail("Handler not dead! It should not have survived this!")
     end,
@@ -1234,11 +1228,15 @@ handler_requests_under_load(Config) ->
                                        flush_qlen => 2000,
                                        burst_limit_enable => false}},
     ok = logger:update_handler_config(?MODULE, NewHConfig),
-    Pid = spawn_link(fun() -> send_requests(?MODULE, 1, [{filesync,[]},
-                                                         {info,[]},
-                                                         {reset,[]},
-                                                         {change_config,[]}])
-                     end),
+    Pid = spawn_link(
+            fun() -> send_requests(1,[{logger_std_h,filesync,[?MODULE],[]},
+                                      {logger_olp,info,[h_proc_name()],[]},
+                                      {logger_olp,reset,[h_proc_name()],[]},
+                                      {logger,update_handler_config,
+                                       [?MODULE, config,
+                                        #{overload_kill_enable => false}],
+                                       []}])
+            end),
     Sent = send_burst({t,10000}, seq, {chars,79}, notice),
     Pid ! {self(),finish},
     ReqResult = receive {Pid,Result} -> Result end,
@@ -1249,8 +1247,9 @@ handler_requests_under_load(Config) ->
                         [E || E <- Res,
                               is_tuple(E) andalso (element(1,E) == error)]
                 end,
-    Errors = [{Req,FindError(Res)} || {Req,Res} <- ReqResult],
-    NoOfReqs = lists:foldl(fun({_,Res}, N) -> N + length(Res) end, 0, ReqResult),
+    Errors = [{Func,FindError(Res)} || {_,Func,_,Res} <- ReqResult],
+    NoOfReqs = lists:foldl(fun({_,_,_,Res}, N) -> N + length(Res) end,
+                           0, ReqResult),
     ct:pal("~w requests made. Errors: ~n~p", [NoOfReqs,Errors]),
     ok = file_delete(Log).
 handler_requests_under_load(cleanup, _Config) ->
@@ -1272,22 +1271,14 @@ recreate_deleted_log(cleanup, _Config) ->
 
 %%%-----------------------------------------------------------------
 %%%
-send_requests(HName, TO, Reqs = [{Req,Res}|Rs]) ->
+send_requests(TO, Reqs = [{Mod,Func,Args,Res}|Rs]) ->
     receive
         {From,finish} ->
             From ! {self(),Reqs}
     after
         TO ->
-            Result =
-                case Req of
-                    change_config ->
-                        logger:update_handler_config(HName, config,
-                                                     #{overload_kill_enable =>
-                                                           false});
-                    Func ->
-                        logger_std_h:Func(HName)
-                end,
-            send_requests(HName, TO, Rs ++ [{Req,[Result|Res]}])
+            Result = apply(Mod,Func,Args),
+            send_requests(TO, Rs ++ [{Mod,Func,Args,[Result|Res]}])
     end.
             
 
@@ -1624,7 +1615,8 @@ start_tracer(Trace,Expected) ->
     Pid = self(),
     FileCtrlPid = maps:get(file_ctrl_pid,
                            maps:get(handler_state,
-                                    logger_std_h:info(?MODULE))),
+                                    maps:get(cb_state,
+                                             logger_olp:info(h_proc_name())))),
     dbg:tracer(process,{fun tracer/2,{Pid,Expected}}),
     dbg:p(whereis(h_proc_name()),[c]),
     dbg:p(FileCtrlPid,[c]),
@@ -1632,7 +1624,9 @@ start_tracer(Trace,Expected) ->
     ok.
 
 tpl([{M,F,A}|Trace]) ->
-    {ok,Match} = dbg:tpl(M,F,A,[]),
+    tpl([{{M,F,A},[]}|Trace]);
+tpl([{{M,F,A},MS}|Trace]) ->
+    {ok,Match} = dbg:tpl(M,F,A,MS),
     case lists:keyfind(matched,1,Match) of
         {_,_,1} ->
             ok;
diff --git a/lib/kernel/test/logger_stress_SUITE.erl b/lib/kernel/test/logger_stress_SUITE.erl
new file mode 100644
index 0000000000..4072e8c86a
--- /dev/null
+++ b/lib/kernel/test/logger_stress_SUITE.erl
@@ -0,0 +1,456 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2018. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+-module(logger_stress_SUITE).
+
+-compile(export_all).
+
+-include_lib("common_test/include/ct_event.hrl").
+-include_lib("kernel/include/logger.hrl").
+-include_lib("kernel/src/logger_h_common.hrl").
+
+-ifdef(SAVE_STATS).
+  -define(COLLECT_STATS(_All_,_Procs_),
+          ct:pal("~p",[stats(_All_,_Procs_)])).
+-else.
+  -define(COLLECT_STATS(_All_,_Procs__), ok).
+-endif.
+
+-define(TEST_DURATION,120). % seconds
+
+suite() ->
+    [{timetrap,{minutes,3}},
+     {ct_hooks,[logger_test_lib]}].
+
+init_per_suite(Config) ->
+    Config.
+
+end_per_suite(_Config) ->
+    ok.
+
+init_per_group(_Group, Config) ->
+    Config.
+
+end_per_group(_Group, _Config) ->
+    ok.
+
+init_per_testcase(_TestCase, Config) ->
+    Config.
+
+end_per_testcase(Case, Config) ->
+    try apply(?MODULE,Case,[cleanup,Config])
+    catch error:undef -> ok
+    end,
+    ok.
+
+groups() ->
+    [].
+
+all() -> 
+    [allow_events,
+     reject_events,
+     std_handler,
+     disk_log_handler,
+     emulator_events,
+     remote_events,
+     remote_to_disk_log,
+     remote_emulator_events,
+     remote_emulator_to_disk_log].
+
+%%%-----------------------------------------------------------------
+%%% Test cases
+%%%-----------------------------------------------------------------
+%% Time from log macro call to handler callback
+allow_events(Config) ->
+    {ok,_,Node} =
+        logger_test_lib:setup(Config,
+                              [{logger,
+                                [{handler,default,?MODULE,#{}}]},
+                               {logger_level,notice}]),
+    N = 100000,
+    {T,_} = timer:tc(fun() -> rpc:call(Node,?MODULE,nlogs,[N]) end),
+    IOPS = N * 1000/T, % log events allowed per millisecond
+    ct_event:notify(#event{name = benchmark_data,
+                           data = [{value,IOPS}]}),
+    {comment,io_lib:format("~.2f accepted events pr millisecond",
+                           [IOPS])}.
+
+%% Time from log macro call to reject (log level)
+reject_events(Config) ->
+    {ok,_,Node} =
+        logger_test_lib:setup(Config,
+                              [{logger,
+                                [{handler,default,?MODULE,#{}}]},
+                               {logger_level,error}]),
+    N = 1000000,
+    {T,_} = timer:tc(fun() -> rpc:call(Node,?MODULE,nlogs,[N]) end),
+    IOPS = N * 1000/T, % log events rejected per millisecond
+    ct_event:notify(#event{name = benchmark_data,
+                           data = [{value,IOPS}]}),
+    {comment,io_lib:format("~.2f rejected events pr millisecond",
+                           [IOPS])}.
+
+%% Cascading failure that produce gen_server and proc_lib reports -
+%% how many of the produced log events are actually written to a log
+%% with logger_std_h file handler.
+std_handler(Config) ->
+    {ok,_,Node} =
+        logger_test_lib:setup(Config,
+                              [{logger,
+                                [{handler,default,logger_std_h,
+                                  #{config=>#{type=>{file,"default.log"}}}}]}]),
+
+    cascade({Node,{logger_backend,log_allowed,2},[]},
+            {Node,{logger_std_h,write,4},[{default,logger_std_h_default}]},
+            fun otp_cascading/0).
+std_handler(cleanup,_Config) ->
+    _ = file:delete("default.log"),
+    ok.
+
+%% Cascading failure that produce gen_server and proc_lib reports -
+%% how many of the produced log events are actually written to a log
+%% with logger_disk_log_h wrap file handler.
+disk_log_handler(Config) ->
+    {ok,_,Node} =
+        logger_test_lib:setup(Config,
+                              [{logger,
+                                [{handler,default,logger_disk_log_h,#{}}]}]),
+    cascade({Node,{logger_backend,log_allowed,2},[]},
+            {Node,{logger_disk_log_h,write,4},
+             [{default,logger_disk_log_h_default}]},
+            fun otp_cascading/0).
+disk_log_handler(cleanup,_Config) ->
+    Files = filelib:wildcard("default.log.*"),
+    [_ = file:delete(F) || F <- Files],
+    ok.
+
+%% Cascading failure that produce log events from the emulator - how
+%% many of the produced log events pass through the proxy.
+emulator_events(Config) ->
+    {ok,_,Node} =
+        logger_test_lib:setup(Config,
+                              [{logger,
+                                [{handler,default,?MODULE,#{}}]}]),
+    cascade({Node,{?MODULE,producer,0},[]},
+            {Node,{?MODULE,log,2},[{proxy,logger_proxy}]},
+            fun em_cascading/0).
+
+%% Cascading failure that produce gen_server and proc_lib reports on
+%% remote node - how many of the produced log events pass through the
+%% proxy.
+remote_events(Config) ->
+    {ok,_,Node1} =
+        logger_test_lib:setup([{postfix,1}|Config],
+                              [{logger,
+                                [{handler,default,?MODULE,#{}}]}]),
+    {ok,_,Node2} =
+        logger_test_lib:setup([{postfix,2}|Config],[]),
+    cascade({Node2,{logger_backend,log_allowed,2},[{remote_proxy,logger_proxy}]},
+            {Node1,{?MODULE,log,2},[{local_proxy,logger_proxy}]},
+            fun otp_cascading/0).
+
+%% Cascading failure that produce gen_server and proc_lib reports on
+%% remote node - how many of the produced log events are actually
+%% written to a log with logger_disk_log_h wrap file handler.
+remote_to_disk_log(Config) ->
+    {ok,_,Node1} =
+        logger_test_lib:setup([{postfix,1}|Config],
+                              [{logger,
+                                [{handler,default,logger_disk_log_h,#{}}]}]),
+    {ok,_,Node2} =
+        logger_test_lib:setup([{postfix,2}|Config],[]),
+    cascade({Node2,{logger_backend,log_allowed,2},[{remote_proxy,logger_proxy}]},
+            {Node1,{logger_disk_log_h,write,4},
+             [{local_proxy,logger_proxy},
+              {local_default,logger_disk_log_h_default}]},
+            fun otp_cascading/0).
+remote_to_disk_log(cleanup,_Config) ->
+    Files = filelib:wildcard("default.log.*"),
+    [_ = file:delete(F) || F <- Files],
+    ok.
+
+%% Cascading failure that produce log events from the emulator on
+%% remote node - how many of the produced log events pass through the
+%% proxy.
+remote_emulator_events(Config) ->
+    {ok,_,Node1} =
+        logger_test_lib:setup([{postfix,1}|Config],
+                              [{logger,
+                                [{handler,default,?MODULE,#{}}]}]),
+    {ok,_,Node2} =
+        logger_test_lib:setup([{postfix,2}|Config],[]),
+    cascade({Node2,{?MODULE,producer,0},[{remote_proxy,logger_proxy}]},
+            {Node1,{?MODULE,log,2},[{local_proxy,logger_proxy}]},
+            fun em_cascading/0).
+
+%% Cascading failure that produce log events from the emulator on
+%% remote node - how many of the produced log events are actually
+%% written to a log with logger_disk_log_h wrap file handler.
+remote_emulator_to_disk_log(Config) ->
+    {ok,_,Node1} =
+        logger_test_lib:setup([{postfix,1}|Config],
+                              [{logger,
+                                [{handler,default,logger_disk_log_h,#{}}]}]),
+    {ok,_,Node2} =
+        logger_test_lib:setup([{postfix,2}|Config],[]),
+    cascade({Node2,{?MODULE,producer,0},[{remote_proxy,logger_proxy}]},
+            {Node1,{logger_disk_log_h,write,4},
+             [{local_proxy,logger_proxy},
+              {local_default,logger_disk_log_h_default}]},
+            fun em_cascading/0).
+remote_emulator_to_disk_log(cleanup,_Config) ->
+    Files = filelib:wildcard("default.log.*"),
+    [_ = file:delete(F) || F <- Files],
+    ok.
+
+%%%-----------------------------------------------------------------
+%%% Internal functions
+nlogs(N) ->
+    group_leader(whereis(user),self()),
+    Str = "\"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+        "[\\]^_`abcdefghijklmnopqr",
+    [?LOG_NOTICE(Str) || _ <- lists:seq(1,N)],
+    ok.
+
+%% cascade(ProducerInfo,ConsumerInfo,TestFun)
+cascade({PNode,PMFA,_PStatProcs},{CNode,CMFA,_CStatProcs},TestFun) ->
+    Tab  = ets:new(counter,[set,public]),
+    ets:insert(Tab,{producer,0}),
+    ets:insert(Tab,{consumer,0}),
+    dbg:tracer(process,{fun tracer/2,{Tab,PNode,CNode}}),
+    dbg:n(PNode),
+    dbg:n(CNode),
+    dbg:cn(node()),
+    dbg:p(all,[call,arity]),
+    dbg:tpl(PMFA,[]),
+    dbg:tpl(CMFA,[]),
+
+    Pid = rpc:call(CNode,?MODULE,wrap_test,[PNode,TestFun]),
+    MRef = erlang:monitor(process,Pid),
+    TO = ?TEST_DURATION*1000,
+    receive {'DOWN',MRef,_,_,Reason} ->
+            ct:fail({remote_pid_down,Reason})
+    after TO ->
+            All = ets:lookup_element(Tab,producer,2),
+            Written = ets:lookup_element(Tab,consumer,2),
+            dbg:stop_clear(),
+            ?COLLECT_STATS(All,
+                           [{PNode,P,Id} || {Id,P} <- _PStatProcs] ++
+                               [{CNode,P,Id} || {Id,P} <- _CStatProcs]),
+            Ratio = Written/All * 100,
+            ct_event:notify(#event{name = benchmark_data,
+                                   data = [{value,Ratio}]}),
+            {comment,io_lib:format("~p % (~p written, ~p produced)",
+                                   [round(Ratio),Written,All])}
+    end.
+
+wrap_test(Fun) ->
+    wrap_test(node(),Fun).
+wrap_test(Node,Fun) ->
+    reset(),
+    group_leader(whereis(user),self()),
+    rpc:call(Node,?MODULE,do_fun,[Fun]).
+
+do_fun(Fun) ->
+    reset(),
+    Fun().
+
+reset() ->
+    reset([logger_std_h_default, logger_disk_log_h_default, logger_proxy]).
+reset([P|Ps]) ->
+    is_pid(whereis(P)) andalso logger_olp:reset(P),
+    reset(Ps);
+reset([]) ->
+    ok.
+
+
+tracer({trace,_,call,{?MODULE,producer,_}},{Tab,_PNode,_CNode}=S) ->
+    ets:update_counter(Tab,producer,1),
+    S;
+tracer({trace,Pid,call,{logger_backend,log_allowed,_}},{Tab,PNode,_CNode}=S) when node(Pid)=:=PNode ->
+    ets:update_counter(Tab,producer,1),
+    S;
+tracer({trace,_,call,{?MODULE,log,_}},{Tab,_PNode,_CNode}=S) ->
+    ets:update_counter(Tab,consumer,1),
+    S;
+tracer({trace,_,call,{_,write,_}},{Tab,_PNode,_CNode}=S) ->
+    ets:update_counter(Tab,consumer,1),
+    S;
+tracer(_,S) ->
+    S.
+
+
+%%%-----------------------------------------------------------------
+%%% Collect statistics
+-define(STAT_KEYS,
+        [burst_drops,
+         calls,
+         casts,
+         drops,
+         flushed,
+         flushes,
+         freq,
+         last_qlen,
+         max_qlen,
+         time,
+         writes]).
+-define(EVENT_KEYS,
+        [calls,casts,flushed]).
+
+stats(All,Procs) ->
+    NI = [{Id,rpc:call(N,logger_olp,info,[P])} || {N,P,Id}<-Procs],
+    [{all,All}|[stats(Id,I,All) || {Id,I} <- NI]].
+
+stats(Id,Info,All) ->
+    S = maps:with(?STAT_KEYS,Info),
+    AllOnProc = lists:sum(maps:values(maps:with(?EVENT_KEYS,S))),
+    if All>0 ->
+            Writes = maps:get(writes,S),
+            {_,ActiveTime} = maps:get(time,S),
+            Rate = round(100*Writes/All),
+            RateOnProc =
+                if AllOnProc>0 ->
+                        round(100*Writes/AllOnProc);
+                   true ->
+                        0
+                end,
+            AvFreq =
+                if ActiveTime>0 ->
+                        round(Writes/ActiveTime);
+                   true ->
+                        0
+                end,
+            {Id,
+             {stats,S},
+             {rate,Rate},
+             {rate_on_proc,RateOnProc},
+             {av_freq,AvFreq}};
+       true ->
+            {Id,none}
+    end.
+
+%%%-----------------------------------------------------------------
+%%% Spawn a lot of processes that crash repeatedly, causing a lot of
+%%% error reports from the emulator.
+em_cascading() ->
+    spawn(fun() -> super() end).
+
+super() ->
+    process_flag(trap_exit,true),
+    spawn_link(fun server/0),
+    [spawn_link(fun client/0) || _<-lists:seq(1,10000)],
+    super_loop().
+
+super_loop() ->
+    receive
+        {'EXIT',_,server} ->
+            spawn_link(fun server/0),
+            super_loop();
+        {'EXIT',_,_} ->
+            _L = lists:sum(lists:seq(1,10000)),
+            spawn_link(fun client/0),
+            super_loop()
+    end.
+
+client() ->
+    receive
+    after 1 ->
+            case whereis(server) of
+                Pid when is_pid(Pid) ->
+                    ok;
+                undefined ->
+                    producer(),
+                    erlang:error(some_exception)
+            end
+    end,
+    client().
+
+server() ->
+    register(server,self()),
+    receive
+    after 3000 ->
+            exit(server)
+    end.
+        
+
+%%%-----------------------------------------------------------------
+%%% Create a supervisor tree with processes that crash repeatedly,
+%%% causing a lot of supervisor reports and crashreports
+otp_cascading() ->
+    {ok,Pid} = supervisor:start_link({local,otp_super}, ?MODULE, [otp_super]),
+    unlink(Pid),
+    Pid.
+
+otp_server_sup() ->
+    supervisor:start_link({local,otp_server_sup},?MODULE,[otp_server_sup]).
+
+otp_client_sup(N) ->
+    supervisor:start_link({local,otp_client_sup},?MODULE,[otp_client_sup,N]).
+
+otp_server() ->
+    gen_server:start_link({local,otp_server},?MODULE,[otp_server],[]).
+
+otp_client() ->
+    gen_server:start_link(?MODULE,[otp_client],[]).
+
+init([otp_super]) ->
+    {ok, {{one_for_one, 200, 10},
+            [{client_sup,
+                    {?MODULE, otp_client_sup, [10000]},
+                    permanent, 1000, supervisor, [?MODULE]},
+             {server_sup,
+                    {?MODULE, otp_server_sup, []},
+                    permanent, 1000, supervisor, [?MODULE]}
+            ]}};
+init([otp_server_sup]) ->
+    {ok, {{one_for_one, 2, 10},
+            [{server,
+                    {?MODULE, otp_server, []},
+                    permanent, 1000, worker, [?MODULE]}
+            ]}};
+init([otp_client_sup,N]) ->
+    spawn(fun() ->
+                  [supervisor:start_child(otp_client_sup,[])
+                   || _ <- lists:seq(1,N)]
+          end),
+    {ok, {{simple_one_for_one, N*10, 1},
+            [{client,
+                    {?MODULE, otp_client, []},
+                    permanent, 1000, worker, [?MODULE]}
+            ]}};
+init([otp_server]) ->
+    {ok, server, 10000};
+init([otp_client]) ->
+    {ok, client,1}.
+
+handle_info(timeout, client) ->
+    true = is_pid(whereis(otp_server)),
+    {noreply,client,1};
+handle_info(timeout, server) ->
+    exit(self(), some_error).
+
+%%%-----------------------------------------------------------------
+%%% Logger callbacks
+log(_LogEvent,_Config) ->
+    ok.
+
+%%%-----------------------------------------------------------------
+%%% Function to trace on for counting produced emulator messages
+producer() ->
+    ok.
diff --git a/lib/kernel/test/logger_test_lib.erl b/lib/kernel/test/logger_test_lib.erl
index 81eb9ce5eb..be4bc427fb 100644
--- a/lib/kernel/test/logger_test_lib.erl
+++ b/lib/kernel/test/logger_test_lib.erl
@@ -28,11 +28,17 @@
          post_end_per_testcase/5, post_end_per_suite/3]).
 
 setup(Config,Vars) ->
+    Postfix = case proplists:get_value(postfix, Config) of
+                  undefined -> "";
+                  P -> ["_",P]
+              end,
     FuncStr = lists:concat([proplists:get_value(suite, Config), "_",
-                            proplists:get_value(tc, Config)]),
+                            proplists:get_value(tc, Config)|
+                            Postfix]),
     ConfigFileName = filename:join(proplists:get_value(priv_dir, Config), FuncStr),
     file:write_file(ConfigFileName ++ ".config", io_lib:format("[{kernel, ~p}].",[Vars])),
-    case test_server:start_node(proplists:get_value(tc, Config), slave,
+    Sname = lists:concat([proplists:get_value(tc,Config)|Postfix]),
+    case test_server:start_node(Sname, slave,
                                 [{args, ["-pa ",filename:dirname(code:which(?MODULE)),
                                          " -boot start_sasl -kernel start_timer true "
                                          "-config ",ConfigFileName]}]) of
diff --git a/lib/tools/priv/styles.css b/lib/tools/priv/styles.css
index e10e94e3ad..d4e3d79596 100644
--- a/lib/tools/priv/styles.css
+++ b/lib/tools/priv/styles.css
@@ -53,10 +53,12 @@ table thead {
   display: none;
 }
 table td.line,
+table td.line a,
 table td.hits {
   width: 20px;
   background: #eaeaea;
   text-align: center;
+  text-decoration: none;
   font-size: 11px;
   padding: 0 10px;
   color: #949494;
@@ -68,6 +70,7 @@ table td.hits {
   background-color: #f0f0f0;
 }
 tr.miss td.line,
+tr.miss td.line a,
 tr.miss td.hits {
   background-color: #ffdce0;
   border-color: #fdaeb7;
@@ -76,6 +79,7 @@ tr.miss td {
   background-color: #ffeef0;
 }
 tr.hit td.line,
+tr.hit td.line a,
 tr.hit td.hits {
   background-color: #cdffd8;
   border-color: #bef5cb;
diff --git a/lib/tools/src/cover.erl b/lib/tools/src/cover.erl
index d7269e3f27..4f3707d2ed 100644
--- a/lib/tools/src/cover.erl
+++ b/lib/tools/src/cover.erl
@@ -2563,8 +2563,9 @@ table_row(Line, L) ->
 table_data(Line, L, N) ->
    LineNoNL = Line -- "\n",
    ["<td class=\"line\" id=\"L",integer_to_list(L),"\">",
+    "<a href=\"#L",integer_to_list(L),"\">",
     integer_to_list(L),
-    "</td>\n",
+    "</a></td>\n",
    "<td class=\"hits\">",maybe_integer_to_list(N),"</td>\n",
    "<td class=\"source\"><code>",LineNoNL,"</code></td>\n</tr>\n"].