Merge branch 'peppe/kernel/logger_updates'

* peppe/kernel/logger_updates:
  [logger] Correct documentation
  [logger] Update handler documentation
  [logger] Fix test suite compilation warnings
  [logger] Fix failing tests
  [logger] Change overload_kill_restart_after value to infinity
  [logger] Change name of function sync/1 to filesync/1
  [logger] Reset logger config after tests
  [logger] Don't delete log file of failing test cases
  [logger] Set up priority for processes generatig test bursts
  [logger] Stress overload_kill tests a bit more
  [logger] Remove some compiler warnings in test suites
  [logger] Sort keys when testing formatter template
  [logger] Skip test involving file access rights on windows
  [logger] Skip some overload protection tests when using dirty schedulers

15 files changed, 490 insertions, 387 deletions

diff --git a/lib/kernel/doc/src/logger_chapter.xml b/lib/kernel/doc/src/logger_chapter.xml
index f7df0a3e6e..a4951022bb 100644
--- a/lib/kernel/doc/src/logger_chapter.xml
+++ b/lib/kernel/doc/src/logger_chapter.xml
@@ -97,6 +97,7 @@
       defined.</p>
   </section>
   <section>
+    <marker id="logger_api"/>
     <title>Logger API</title>
     <p>The API for logging consists of a set
       of <seealso marker="logger#macros">macros</seealso>, and a set
@@ -1103,184 +1104,210 @@ do_log(Fd, LogEvent, #{formatter := {FModule, FConfig}}) ->
   <section>
     <marker id="overload_protection"/>
     <title>Protecting the Handler from Overload</title>
-    <p>In order for the built-in handlers to survive, and stay responsive,
-    during periods of high load (i.e. when huge numbers of incoming
-    log requests must be handled), a mechanism for overload protection
-    has been implemented in the
-    <seealso marker="logger_std_h"><c>logger_std_h</c></seealso>
-    and <seealso marker="logger_disk_log_h"><c>logger_disk_log_h</c>
-    </seealso> handler. The mechanism, used by both handlers, works
-    as follows:</p>
+    <p>The default handlers, <seealso marker="logger_std_h">
+    <c>logger_std_h</c></seealso> and <seealso marker="logger_disk_log_h">
+    <c>logger_disk_log_h</c></seealso>, feature an overload protection
+    mechanism, which makes it possible for the handlers to survive,
+    and stay responsive, during periods of high load (when huge
+    numbers of incoming log requests must be handled).
+    The mechanism works as follows:</p>
     
     <section>
       <title>Message Queue Length</title>
       <p>The handler process keeps track of the length of its message
-      queue and reacts in different ways depending on the current status.
-      The purpose is to keep the handler in, or (as quickly as possible),
-      get the handler into, a state where it can keep up with the pace
-      of incoming log requests. The memory usage of the handler must never
-      keep growing larger and larger, since that would eventually cause the
-      handler to crash. Three thresholds with associated actions have been
-      defined:</p>
+      queue and takes some form of action when the current length exceeds a
+      configurable threshold. The purpose is to keep the handler in, or to
+      as quickly as possible get the handler into, a state where it can
+      keep up with the pace of incoming log events. The memory use of the
+      handler must never grow larger and larger, since that will eventually
+      cause the handler to crash. These three thresholds, with associated
+      actions, exist:</p>
       
       <taglist>
-	<tag><c>toggle_sync_qlen</c></tag>
+	<tag><c>sync_mode_qlen</c></tag>
 	<item>
-	  <p>The default value of this level is <c>10</c> messages,
-	  and as long as the length of the message queue is lower, all log
-	  requests are handled asynchronously. This simply means that the
-	  process sending the log request (by calling a log function in the
-	  Logger API) does not wait for a response from the handler but
-	  continues executing immediately after the request (i.e. it will not
-	  be affected by the time it takes the handler to print to the log
-	  device). If the message queue grows larger than this value, however,
-	  the handler starts handling the log requests synchronously instead,
-	  meaning the process sending the request will have to wait for a
-	  response. When the handler manages to reduce the message queue to a
-	  level below the <c>toggle_sync_qlen</c> threshold, asynchronous
+	  <p>As long as the length of the message queue is lower than this
+	  value, all log events are handled asynchronously. This means that
+	  the client process sending the log event, by calling a log function
+	  in the <seealso marker="logger_chapter#logger_api">Logger API</seealso>,
+	  does not wait for a response from the handler but continues
+	  executing immediately after the event is sent. It is not affected
+	  by the time it takes the handler to print the event to the log
+	  device. If the message queue grows larger than this value,
+	  the handler starts handling log events synchronously instead,
+	  meaning that the client process sending the event must wait for a
+	  response. When the handler reduces the message queue to a
+	  level below the <c>sync_mode_qlen</c> threshold, asynchronous
 	  operation is resumed. The switch from asynchronous to synchronous
-	  mode will force the logging tempo of few busy senders to slow down,
-	  but cannot protect the handler sufficiently in situations of many
-	  concurrent senders.</p>
+	  mode can slow down the logging tempo of one, or a few, busy senders,
+	  but cannot protect the handler sufficiently in a situation of many
+	  busy concurrent senders.</p>
+	  <p>Defaults to <c>10</c> messages.</p>
 	</item>
-	<tag><c>drop_new_reqs_qlen</c></tag>
+	<tag><c>drop_mode_qlen</c></tag>
 	<item>
-	  <p>When the message queue has grown larger than this threshold, which
-	  defaults to <c>200</c> messages, the handler switches to a mode in
-	  which it drops any new requests being made. Dropping a message in
-	  this state means that the log function never actually sends a message
-	  to the handler. The log call simply returns without an action. When
-	  the length of the message queue has been reduced to a level below this
-	  threshold, synchronous or asynchronous request handling mode is
-	  resumed.</p>
+	  <p>When the message queue grows larger than this threshold, the
+	  handler switches to a mode in which it drops all new events that
+	  senders want to log. Dropping an event in this mode means that the
+	  call to the log function never results in a message being sent to
+	  the handler, but the function returns without taking any action.
+	  The handler keeps logging the events that are already in its message
+	  queue, and when the length of the message queue is reduced to a level
+	  below the threshold, synchronous or asynchronous mode is resumed.
+	  Notice that when the handler activates or deactivates drop mode,
+	  information about it is printed in the log.</p>
+	  <p>Defaults to <c>200</c> messages.</p>
 	</item>
-	<tag><c>flush_reqs_qlen</c></tag>
+	<tag><c>flush_qlen</c></tag>
 	<item>
-	  <p>Above this threshold, which defaults to <c>1000</c> messages, a
-	  flush operation takes place, in which all messages buffered in the
-	  process mailbox get deleted without any logging actually taking
-	  place. (Processes waiting for a response from a synchronous log request
-	  will receive a reply indicating that the request has been dropped).</p>
+	  <p>If the length of the message queue grows larger than this threshold,
+	  a flush (delete) operation takes place. To flush events, the handler
+	  discards the messages in the message queue by receiving them in a
+	  loop without logging. Client processes waiting for a response from a
+	  synchronous log request receive a reply from the handler indicating
+	  that the request is dropped. The handler process increases its
+	  priority during the flush loop to make sure that no new events
+	  are received during the operation. Notice that after the flush operation
+	  is performed, the handler prints information in the log about how many
+	  events have been deleted.</p>
+	  <p>Defaults to <c>1000</c> messages.</p>
 	</item>
       </taglist>
 
       <p>For the overload protection algorithm to work properly, it is
       required that:</p>
 
-      <p><c>toggle_sync_qlen =&lt; drop_new_reqs_qlen =&lt; flush_reqs_qlen</c></p>
+      <p><c>sync_mode_qlen =&lt; drop_mode_qlen =&lt; flush_qlen</c></p>
 
       <p>and that:</p>
 
-      <p><c>drop_new_reqs_qlen &gt; 1</c></p>
+      <p><c>drop_mode_qlen &gt; 1</c></p>
 
-      <p>If <c>toggle_sync_qlen</c> is set to <c>0</c>, the handler will handle all
-      requests synchronously. Setting the value of <c>toggle_sync_qlen</c> to the same
-      as <c>drop_new_reqs_qlen</c>, disables the synchronous mode. Likewise, setting
-      the value of <c>drop_new_reqs_qlen</c> to the same as <c>flush_reqs_qlen</c>,
-      disables the drop mode.</p>
+      <p>To disable certain modes, do the following:</p>
+      <list>
+	<item>If <c>sync_mode_qlen</c> is set to <c>0</c>, all log events are handled
+	synchronously. That is, asynchronous logging is disabled.</item>
+	<item>If <c>sync_mode_qlen</c> is set to the same value as
+	<c>drop_mode_qlen</c>, synchronous mode is disabled. That is, the handler
+	always runs in asynchronous mode, unless dropping or flushing is invoked.</item>
+	<item>If <c>drop_mode_qlen</c> is set to the same value as <c>flush_qlen</c>,
+	drop mode is disabled and can never occur.</item>
+      </list>
 
       <p>During high load scenarios, the length of the handler message queue
       rarely grows in a linear and predictable way. Instead, whenever the
-      handler process gets scheduled in, it can have an almost arbitrary number
-      of messages waiting in the mailbox. It's for this reason that the overload
-      protection mechanism is focused on acting quickly and quite drastically
-      (such as immediately dropping or flushing messages) as soon as a large
-      queue length is detected. </p>
-
-      <p>The thresholds listed above may be modified by the user if, e.g, a handler
-      shouldn't drop or flush messages unless the message queue length grows
-      extremely large. (The handler must be allowed to use large amounts of memory
-      under such circumstances however). Another example of when the user might want
-      to change the settings is if, for performance reasons, the logging processes must
-      never get blocked by synchronous log requests, while dropping or flushing requests
-      is perfectly acceptable (since it doesn't affect the performance of the
-      loggers).</p>
+      handler process is scheduled in, it can have an almost arbitrary number
+      of messages waiting in the message queue. It is for this reason that the overload
+      protection mechanism is focused on acting quickly, and quite drastically,
+      such as immediately dropping or flushing messages, when a large queue length
+      is detected.</p>
+
+      <p>The values of the previously listed thresholds can be specified by the user.
+      This way, a handler can be configured to, for example, not drop or flush
+      messages unless the message queue length of the handler process grows extremely
+      large. Notice that large amounts of memory can be required for the node under such
+      circumstances. Another example of user configuration is when, for performance
+      reasons, the client processes must never be blocked by synchronous log requests.
+      It is possible, perhaps, that dropping or flushing events is still acceptable, since
+      it does not affect the performance of the client processes sending the log events.</p>
 
       <p>A configuration example:</p>
       <code type="none">
 logger:add_handler(my_standard_h, logger_std_h,
-                   #{config =>
-                         #{type => {file,"./system_info.log"},
-                           toggle_sync_qlen => 100,
-                           drop_new_reqs_qlen => 1000,
-                           flush_reqs_qlen => 2000}}).
+                   #{config => #{type => {file,"./system_info.log"},
+                                 sync_mode_qlen => 100,
+                                 drop_mode_qlen => 1000,
+                                 flush_qlen => 2000}}).
     </code>
     </section>
 
     <section>
       <title>Controlling Bursts of Log Requests</title>
-      <p>A potential problem with large bursts of log requests, is that log files
-      may get full or wrapped too quickly (in the latter case overwriting
-      previously logged data that could be of great importance). For this reason,
-      both built-in handlers offer the possibility to set a maximum level of how
-      many requests to process with a certain time frame. With this burst control
-      feature enabled, the handler will take care of bursts of log requests
-      without choking log files, or the terminal, with massive amounts of
-      printouts. These are the configuration parameters:</p>
-      
+      <p>Large bursts of log events - many events received by the handler
+      under a short period of time - can potentially cause problems, such as:</p>
+      <list>
+	<item>Log files grow very large, very quickly.</item>
+	<item>Circular logs wrap too quickly so that important data is overwritten.</item>
+	<item>Write buffers grow large, which slows down file sync operations.</item>
+      </list>
+
+      <p>For this reason, both built-in handlers offer the possibility to specify the
+      maximum number of events to be handled within a certain time frame.
+      With this burst control feature enabled, the handler can avoid choking the log with
+      massive amounts of printouts. The configuration parameters are:</p>
       <taglist>
-	<tag><c>enable_burst_limit</c></tag>
+	<tag><c>burst_limit_enable</c></tag>
 	<item>
-	  <p>This is set to <c>true</c> by default. The value <c>false</c>
-	  disables the burst control feature.</p>
+	  <p>Value <c>true</c> enables burst control and <c>false</c> disables it.</p>
+	  <p>Defaults to <c>true</c>.</p>
 	</item>
-	<tag><c>burst_limit_size</c></tag>
+	<tag><c>burst_limit_max_count</c></tag>
 	<item>
-	  <p>This is how many requests should be processed within the
-	  <c>burst_window_time</c> time frame. After this maximum has been
-	  reached, successive requests will be dropped until the end of the
-	  time frame. The default value is <c>500</c> messages.</p>
+	  <p>This is the maximum number of events to handle within a
+	  <c>burst_limit_window_time</c> time frame. After the limit is
+	  reached, successive events are dropped until the end of the time frame.</p>
+	  <p>Defaults to <c>500</c> events.</p>
 	</item>
-	<tag><c>burst_window_time</c></tag>
+	<tag><c>burst_limit_window_time</c></tag>
 	<item>
-	  <p>The default window is <c>1000</c> milliseconds long.</p>
+	  <p>See the previous description of <c>burst_limit_max_count</c>.</p>
+	  <p>Defaults to <c>1000</c> milliseconds.</p>
 	</item>
       </taglist>
 
       <p>A configuration example:</p>
       <code type="none">
 logger:add_handler(my_disk_log_h, logger_disk_log_h,
-                   #{disk_log_opts =>
-                         #{file => "./my_disk_log"},
-                     config =>
-                         #{burst_limit_size => 10,
-                           burst_window_time => 500}}).
+                   #{config => #{file => "./my_disk_log",
+                                 burst_limit_enable => true,
+                                 burst_limit_max_count => 20,
+                                 burst_limit_window_time => 500}}).
     </code>
     </section>
 
     <section>
-      <title>Terminating a Large Handler</title>
-      <p>A handler process may grow large even if it can manage peaks of high load
-      without crashing. The overload protection mechanism includes user configurable
-      levels for a maximum allowed message queue length and maximum allowed memory
-      usage. This feature is disabled by default, but can be switched on by means
-      of the following configuration parameters:</p>
-      
+      <title>Terminating an Overloaded Handler</title>
+      <p>It is possible that a handler, even if it can successfully manage peaks
+      of high load without crashing, can build up a large message queue, or use a
+      large amount of memory. The overload protection mechanism includes an
+      automatic termination and restart feature for the purpose of guaranteeing
+      that a handler does not grow out of bounds. The feature is configured
+      with the following parameters:</p>
       <taglist>
-	<tag><c>enable_kill_overloaded</c></tag>
+	<tag><c>overload_kill_enable</c></tag>
 	<item>
-	  <p>This is set to <c>false</c> by default. The value <c>true</c>
-	  enables the feature.</p>
+	  <p>Value <c>true</c> enables the feature and <c>false</c> disables it.</p>
+	  <p>Defaults to <c>false</c>.</p>
 	</item>
-	<tag><c>handler_overloaded_qlen</c></tag>
+	<tag><c>overload_kill_qlen</c></tag>
 	<item>
-	  <p>This is the maximum allowed queue length. If the mailbox grows larger
-	  than this, the handler process gets terminated.</p>
+	  <p>This is the maximum allowed queue length. If the message queue grows
+	  larger than this, the handler process is terminated.</p>
+	  <p>Defaults to <c>20000</c> messages.</p>
 	</item>
-	<tag><c>handler_overloaded_mem</c></tag>
+	<tag><c>overload_kill_mem_size</c></tag>
 	<item>
-	  <p>This is the maximum allowed memory usage of the handler process. If
-	  the handler grows any larger, the process gets terminated.</p>
+	  <p>This is the maximum memory size that the handler process is allowed to use.
+	  If the handler grows larger than this, the process is terminated.</p>
+	  <p>Defaults to <c>3000000</c> bytes.</p>
 	</item>
-	<tag><c>handler_restart_after</c></tag>
+	<tag><c>overload_kill_restart_after</c></tag>
 	<item>
-	  <p>If the handler gets terminated because of its queue length or
-	  memory usage, it can get automatically restarted again after a
-	  configurable delay time. The time is specified in milliseconds
-	  and <c>5000</c> is the default value. The value <c>never</c> can
-	  also be set, which prevents a restart.</p>
+	  <p>If the handler is terminated, it restarts automatically after a
+	  delay specified in milliseconds. The value <c>infinity</c> prevents
+	  restarts.</p>
+	  <p>Defaults to <c>5000</c> milliseconds.</p>
 	</item>
       </taglist>
+      <p>If the handler process is terminated because of overload, it prints
+      information about it in the log. It also prints information about when a
+      restart has taken place, and the handler is back in action.</p>
+      <note>
+	<p>The sizes of the log events affect the memory needs of the handler.
+	For information about how to limit the size of log events, see the
+	<seealso marker="logger_formatter"><c>logger_formatter(3)</c></seealso>
+	manual page.</p>
+      </note>
     </section>
   </section>
 
diff --git a/lib/kernel/doc/src/logger_disk_log_h.xml b/lib/kernel/doc/src/logger_disk_log_h.xml
index 63c29cb010..98439983cf 100644
--- a/lib/kernel/doc/src/logger_disk_log_h.xml
+++ b/lib/kernel/doc/src/logger_disk_log_h.xml
@@ -33,106 +33,112 @@
     <file>logger_disk_log_h.xml</file>
   </header>
   <module>logger_disk_log_h</module>
-  <modulesummary>A disk_log based handler for the Logger.</modulesummary>
+  <modulesummary>A disk_log based handler for Logger</modulesummary>
 
   <description>
     <p>This is a handler for Logger that offers circular
     (wrapped) logs by using <seealso marker="disk_log"><c>disk_log</c></seealso>. 
-    Multiple instances
-    of this handler can be added to Logger, and each instance prints to
-    its own disk_log file, created with the name and settings specified in
-    the handler configuration.</p>
+    Multiple instances of this handler can be added to Logger, and each instance
+    prints to its own disk log file, created with the name and settings specified
+    in the handler configuration.</p>
     <p>The default standard handler,
     <seealso marker="logger_std_h"><c>logger_std_h</c></seealso>, can be
-    replaced by a disk_log handler at start up of the Kernel application.
+    replaced by a disk_log handler at startup of the Kernel application.
     See an example of this below.</p>
-    <p>The handler has an overload protection mechanism that will keep the handler
-    process and the Kernel application alive during a high load of log 
-    requests. How this feature works, and how to modify the configuration,
-    is described in the
+    <p>The handler has an overload protection mechanism that keeps the handler
+    process and the Kernel application alive during  high loads of log 
+    events. How overload protection works, and how to configure it, is
+    described in the
     <seealso marker="logger_chapter#overload_protection"><c>User's Guide</c>
     </seealso>.</p>
     <p>To add a new instance of the disk_log handler, use
     <seealso marker="logger#add_handler-3"><c>logger:add_handler/3</c>
-    </seealso>. The handler configuration argument is a map which may contain
+    </seealso>. The handler configuration argument is a map which can contain
     general configuration parameters, as documented in the
     <seealso marker="logger_chapter#handler_configuration"><c>User's Guide</c>
-    </seealso>, as well as handler specific parameters.</p>
-    <p>The settings for the disk_log log file should be specified with the
-    key <c>disk_log_opts</c>. These settings are a subset of the disk_log
-    data type
-    <seealso marker="disk_log#open-1"><c>dlog_option()</c></seealso>.</p>
-    <p>Parameters in the <c>disk_log_opts</c> map:</p>
+    </seealso>, and handler specific parameters. The specific data
+    is stored in a sub map with the key <c>config</c>, and can contain the
+    following parameters:</p>
     <taglist>
       <tag><c>file</c></tag>
-      <item>This is the full name of the disk_log log file.</item>
+      <item>
+	<p>This is the full name of the disk log file. The option
+	corresponds to the <c>name</c> property in the
+	<seealso marker="disk_log#open-1"><c>dlog_option()</c></seealso>
+	datatype.</p>
+      </item>
       <tag><c>type</c></tag>
-      <item>This is the disk_log type, <c>wrap</c> or <c>halt</c>. The
-      default value is <c>wrap</c>.</item>
+      <item>
+	<p>This is the disk log type, <c>wrap</c> or <c>halt</c>. The option
+	corresponds to the <c>type</c> property in the
+	<seealso marker="disk_log#open-1"><c>dlog_option()</c></seealso>
+	datatype.</p>
+	<p>Defaults to <c>wrap</c>.</p>
+      </item>
       <tag><c>max_no_files</c></tag>
-      <item>This is the maximum number of files that disk_log will use
-      for its circular logging. The default value is <c>10</c>. (The setting
-      has no effect on a halt log).</item>
+      <item>
+	<p>This is the maximum number of files that disk_log uses
+	for its circular logging. The option
+	corresponds to the <c>MaxNoFiles</c> element in the <c>size</c> property in the
+	<seealso marker="disk_log#open-1"><c>dlog_option()</c></seealso>
+	datatype.</p>
+	<p>Defaults to <c>10</c>.</p>
+	<p>The setting has no effect on a halt log.</p>
+      </item>
       <tag><c>max_no_bytes</c></tag>
-      <item>This is the maximum number of bytes that will be written to
-      a log file before disk_log proceeds with the next file in order (or
-      generates an error in case of a full halt log). The default value for
-      a wrap log is <c>1048576</c> bytes, and <c>infinity</c> for a halt
-      log.</item>
-    </taglist>
-    <p>Specific configuration for the handler (represented as a sub map)
-    is specified with the key <c>config</c>. It may contain the
-    following parameter:</p>
-    <taglist>
+      <item>
+	<p>This is the maximum number of bytes that is written to
+	a log file before disk_log proceeds with the next file in order, or
+	generates an error in case of a full halt log. The option
+	corresponds to the <c>MaxNoBytes</c> element in the <c>size</c> property in the
+	<seealso marker="disk_log#open-1"><c>dlog_option()</c></seealso>
+	datatype.</p>
+	<p>Defaults to <c>1048576</c> bytes for a wrap log, and
+	<c>infinity</c> for a halt log.</p>
+      </item>
       <tag><c>filesync_repeat_interval</c></tag>
       <item>
-	<p>This value (in milliseconds) specifies how often the handler will
-	do a disk_log sync operation in order to make sure that buffered data
-	gets written to disk. The handler will repeatedly attempt this
-	operation, but only perform it if something has actually been logged
-	since the last sync. The default value is <c>5000</c> milliseconds.
-	If <c>no_repeat</c> is set as value, the repeated sync operation is
-	disabled. The user can also call the
-	<seealso marker="logger_disk_log_h#sync-1"><c>sync/1</c>
-	</seealso> function to perform a disk_log sync.</p></item>
+	<p>This value, in milliseconds, specifies how often the handler does
+	a disk_log sync operation to write buffered data to disk. The handler attempts
+	the operation repeatedly, but only performs a new sync if something has
+	actually been logged.</p>
+	<p>Defaults to <c>5000</c> milliseconds.</p>
+	<p>If <c>no_repeat</c> is set as value, the repeated sync operation
+	is disabled. The user can also call the
+	<seealso marker="logger_disk_log_h#filesync-1"><c>filesync/1</c>
+	</seealso> function to perform a disk_log sync.</p>
+      </item>
     </taglist>
-    <p>There are a number of other configuration parameters available, that are
-    to be used for customizing the overload protection behaviour. The same
-    parameters are used both in the standard handler and the disk_log handler,
-    and are documented in the
+    <p>Other configuration parameters exist, to be used for customizing
+    the overload protection behaviour. The same parameters are used both in the
+    standard handler and the disk_log handler, and are documented in the
     <seealso marker="logger_chapter#overload_protection"><c>User's Guide</c>
     </seealso>.</p>
-    <p>Note that when changing the configuration of the handler in runtime, by
-    calling
-    <seealso marker="logger#set_handler_config-2"><c>logger:set_handler_config/2
-    or logger:set_handler_config/3</c></seealso>, the <c>disk_log_opts</c>
-    settings may not be modified.</p>
+    <p>Notice that when changing the configuration of the handler in runtime, the
+    disk_log options (<c>file</c>, <c>type</c>, <c>max_no_files</c>,
+    <c>max_no_bytes</c>) must not be modified.</p>
     <p>Example of adding a disk_log handler:</p>
     <code type="none">
 logger:add_handler(my_disk_log_h, logger_disk_log_h,
-                   #{level => error,
-                     filter_default => log,
-                     disk_log_opts =>
-                              #{file => "./my_disk_log",
-                                type => wrap,
-                                max_no_files => 4,
-                                max_no_bytes => 10000},
-                     config =>
-                              #{filesync_repeat_interval => 1000}}).
+                   #{config => #{file => "./my_disk_log",
+                                 type => wrap,
+                                 max_no_files => 4,
+                                 max_no_bytes => 10000},
+                                 filesync_repeat_interval => 1000}}).
     </code>
-    <p>In order to use the disk_log handler instead of the default standard
+    <p>To use the disk_log handler instead of the default standard
     handler when starting an Erlang node, change the Kernel default logger to
-    use disk_log. Example:</p>
+    use <c>logger_disk_log_h</c>. Example:</p>
     <code type="none">
 erl -kernel logger '[{handler,default,logger_disk_log_h,
-                      #{disk_log_opts => #{file => "./system_disk_log"}}}]'
+                      #{config => #{file => "./system_disk_log"}}}]'
     </code>
   </description>
 
   <funcs>
 
     <func>
-      <name name="sync" arity="1" clause_i="1"/>
+      <name name="filesync" arity="1" clause_i="1"/>
       <fsummary>Writes buffered data to disk.</fsummary>
       <desc>
         <p>Write buffered data to disk.</p>
diff --git a/lib/kernel/doc/src/logger_std_h.xml b/lib/kernel/doc/src/logger_std_h.xml
index 89e11389c5..95b4baf160 100644
--- a/lib/kernel/doc/src/logger_std_h.xml
+++ b/lib/kernel/doc/src/logger_std_h.xml
@@ -33,92 +33,84 @@
     <file>logger_std_h.xml</file>
   </header>
   <module>logger_std_h</module>
-  <modulesummary>Default handler for Logger.</modulesummary>
+  <modulesummary>Standard handler for Logger.</modulesummary>
 
   <description>
-    <p>This is the default handler for Logger.
+    <p>This is the standard handler for Logger.
       Multiple instances of this handler can be added to
-      Logger, and each instance will print logs to <c>standard_io</c>,
-      <c>standard_error</c> or to file. The default instance that starts
-      with Kernel is named <c>default</c> - which is the name to be used
-      for reconfiguration.</p>
-    <p>The handler has an overload protection mechanism that will keep the handler
-      process and the Kernel application alive during a high load of log 
-      requests. How this feature works, and how to modify the configuration,
-      is described in the
+      Logger, and each instance prints logs to <c>standard_io</c>,
+      <c>standard_error</c>, or to file.</p>
+    <p>The handler has an overload protection mechanism that keeps the handler
+      process and the Kernel application alive during high loads of log 
+      events. How overload protection works, and how to configure it, is
+      described in the
       <seealso marker="logger_chapter#overload_protection"><c>User's Guide</c>
       </seealso>.</p>
     <p>To add a new instance of the standard handler, use
       <seealso marker="logger#add_handler-3"><c>logger:add_handler/3</c>
-      </seealso>. The handler configuration argument is a map which may contain
-       general configuration parameters, as documented in the
+      </seealso>. The handler configuration argument is a map which can contain
+      general configuration parameters, as documented in the
        <seealso marker="logger_chapter#handler_configuration"><c>User's Guide</c>
-       </seealso>, as well as handler specific parameters. The specific parameters
-       are stored in a sub map with the key <c>config</c>. The following
-       keys and values may be specified:</p>
+       </seealso>, and handler specific parameters. The specific data
+       is stored in a sub map with the key <c>config</c>, and can contain the
+       following parameters:</p>
     <taglist>
       <tag><marker id="type"/><c>type</c></tag>
       <item>
-	<p>This will have the value <c>standard_io</c>, <c>standard_error</c>,
-	<c>{file,LogFileName}</c>, or <c>{file,LogFileName,LogFileOpts}</c>,
-	where <c>standard_io</c> is the default value for type. It's recommended
-	to not specify <c>LogFileOpts</c> if not absolutely necessary. The
-	default options used by the handler to open a file for logging are:
-	<c>raw</c>, <c>append</c> and <c>delayed_write</c>. The standard
-	handler does not have support for circular logging. Use the
-	<seealso marker="logger_disk_log_h"><c>logger_disk_log_h</c>
-	</seealso> handler for this.</p></item>
+	<p>This has the value <c>standard_io</c>, <c>standard_error</c>,
+	<c>{file,LogFileName}</c>, or <c>{file,LogFileName,LogFileOpts}</c>.</p>
+	<p> Defaults to <c>standard_io</c>.</p>
+	<p>It is recommended not to specify <c>LogFileOpts</c> unless absolutely
+	necessary. The default options used by the handler to open a file for logging are
+	<c>raw</c>, <c>append</c>, and <c>delayed_write</c>. Notice that the standard
+	handler does not have support for circular logging. Use the disk_log handler,
+	<seealso marker="logger_disk_log_h"><c>logger_disk_log_h</c></seealso>,
+	for this.</p>
+      </item>
       <tag><c>filesync_repeat_interval</c></tag>
       <item>
-	<p>This value (in milliseconds) specifies how often the handler will
-	do a file sync operation in order to make sure that buffered data gets
-	written to disk. The handler will repeatedly attempt this
-	operation, but only perform it if something has actually been logged
-	since the last sync. The default value is <c>5000</c> milliseconds.
-	If <c>no_repeat</c> is set as value, the repeated file sync operation
-	is disabled, and it will be the operating system settings that determine
-	how quickly or slowly data gets written	to disk. The user can also call
-	the <seealso marker="logger_std_h#sync-1"><c>sync/1</c></seealso>
-        function to perform a file sync.</p></item>
+	<p>This value, in milliseconds, specifies how often the handler does
+	a file sync operation to write buffered data to disk. The handler attempts
+	the operation repeatedly, but only performs a new sync if something has
+	actually been logged.</p>
+	<p>Defaults to <c>5000</c> milliseconds.</p>
+	<p>If <c>no_repeat</c> is set as value, the repeated file sync operation
+	is disabled, and it is the operating system settings that determine
+	how quickly or slowly data is written to disk. The user can also call
+	the <seealso marker="logger_std_h#filesync-1"><c>filesync/1</c></seealso>
+        function to perform a file sync.</p>
+      </item>
     </taglist>
-    <p>There are a number of other configuration parameters available, that are
-    to be used for customizing the overload protection behaviour. The same
-    parameters are used both in the standard handler and the disk_log handler,
-    and are documented in the
+    <p>Other configuration parameters exist, to be used for customizing
+    the overload protection behaviour. The same parameters are used both in the
+    standard handler and the disk_log handler, and are documented in the
     <seealso marker="logger_chapter#overload_protection"><c>User's Guide</c>
     </seealso>.</p>
-    <p>Note that when changing the configuration of the handler in runtime, by
-    calling
-    <seealso marker="logger#set_handler_config-2"><c>logger:set_handler_config/2</c>
-    </seealso>, or
-    <seealso marker="logger#set_handler_config-3"><c>logger:set_handler_config/3</c>
-    </seealso>,
-    the <c>type</c> parameter may not be modified.</p>
+    <p>Notice that if changing the configuration of the handler in runtime,
+    the <c>type</c> parameter must not be modified.</p>
     <p>Example of adding a standard handler:</p>
     <code type="none">
 logger:add_handler(my_standard_h, logger_std_h,
-                   #{level => info,
-                     filter_default => log,
-                     config =>
-		         #{type => {file,"./system_info.log"},
-                           filesync_repeat_interval => 1000}}).
+                   #{config => #{type => {file,"./system_info.log"},
+                                 filesync_repeat_interval => 1000}}).
     </code>
-    <p>In order to configure the default handler (that starts initially with
-    the Kernel application) to log to file instead of <c>standard_io</c>,
-    change the Kernel default logger to use a file. Example:</p>
+    <p>To set the default handler, that starts initially with
+    the Kernel application, to log to file instead of <c>standard_io</c>,
+    change the Kernel default logger configuration. Example:</p>
     <code type="none">
 erl -kernel logger '[{handler,default,logger_std_h,
                       #{config => #{type => {file,"./log.log"}}}}]'
     </code>
     <p>An example of how to replace the standard handler with a disk_log handler
-    at start up can be found in the manual of
-    <seealso marker="logger_disk_log_h"><c>logger_disk_log_h</c></seealso>.</p>
+    at startup is found in the
+    <seealso marker="logger_disk_log_h"><c>logger_disk_log_h</c></seealso>
+    manual.</p>
   </description>
 
   <funcs>
 
     <func>
-      <name name="sync" arity="1" clause_i="1"/>
+      <name name="filesync" arity="1" clause_i="1"/>
       <fsummary>Writes buffered data to disk.</fsummary>
       <desc>
         <p>Write buffered data to disk.</p>
diff --git a/lib/kernel/src/logger_disk_log_h.erl b/lib/kernel/src/logger_disk_log_h.erl
index a074d0210e..f08621c9c5 100644
--- a/lib/kernel/src/logger_disk_log_h.erl
+++ b/lib/kernel/src/logger_disk_log_h.erl
@@ -26,7 +26,7 @@
 -include("logger_h_common.hrl").
 
 %%% API
--export([start_link/3, info/1, sync/1, reset/1]).
+-export([start_link/3, info/1, filesync/1, reset/1]).
 
 %% gen_server callbacks
 -export([init/1, handle_call/3, handle_cast/2, handle_info/2,
@@ -58,19 +58,19 @@ start_link(Name, Config, HandlerState) ->
 
 %%%-----------------------------------------------------------------
 %%%
--spec sync(Name) -> ok | {error,Reason} when
+-spec filesync(Name) -> ok | {error,Reason} when
       Name :: atom(),
       Reason :: handler_busy | {badarg,term()}.
 
-sync(Name) when is_atom(Name) ->
+filesync(Name) when is_atom(Name) ->
     try
         gen_server:call(?name_to_reg_name(?MODULE,Name),
                         disk_log_sync, ?DEFAULT_CALL_TIMEOUT)
     catch
         _:{timeout,_} -> {error,handler_busy}
     end;
-sync(Name) ->
-    {error,{badarg,{sync,[Name]}}}.
+filesync(Name) ->
+    {error,{badarg,{filesync,[Name]}}}.
 
 %%%-----------------------------------------------------------------
 %%%
@@ -704,7 +704,7 @@ disk_log_sync(Name, State) ->
                         ok;
                     _ ->
                         LogOpts = maps:get(log_opts, State),
-                        logger_h_common:error_notify({Name,sync,
+                        logger_h_common:error_notify({Name,filesync,
                                                       LogOpts,
                                                       SyncError})
                 end,
diff --git a/lib/kernel/src/logger_h_common.erl b/lib/kernel/src/logger_h_common.erl
index d556938f02..f9f762405c 100644
--- a/lib/kernel/src/logger_h_common.erl
+++ b/lib/kernel/src/logger_h_common.erl
@@ -115,7 +115,7 @@ check_common_config({overload_kill_qlen,N}) when is_integer(N) ->
 check_common_config({overload_kill_mem_size,N}) when is_integer(N) ->
     valid;
 check_common_config({overload_kill_restart_after,NorA})  when is_integer(NorA);
-                                                              NorA == never ->
+                                                              NorA == infinity ->
     valid;
 
 check_common_config({filesync_repeat_interval,NorA}) when is_integer(NorA);
@@ -261,7 +261,7 @@ flush_log_events(Limit, Limit) ->
     Limit;
 flush_log_events(N, Limit) ->
     %% flush log events but leave other events, such as
-    %% file/disk_log_sync, info and change_config, so that these
+    %% filesync, info and change_config, so that these
     %% have a chance to be processed even under heavy load
     receive
         {'$gen_cast',{log,_}} ->
diff --git a/lib/kernel/src/logger_h_common.hrl b/lib/kernel/src/logger_h_common.hrl
index ad80b51109..e0a7b6e3ca 100644
--- a/lib/kernel/src/logger_h_common.hrl
+++ b/lib/kernel/src/logger_h_common.hrl
@@ -41,10 +41,10 @@
 -define(OVERLOAD_KILL_MEM_SIZE, 3000000).
 
 %% This is the default time that the handler will wait before
-%% restarting and accepting new requests. The value 'never'
+%% restarting and accepting new requests. The value 'infinity'
 %% disables restarts.
 -define(OVERLOAD_KILL_RESTART_AFTER, 5000).
-%%-define(OVERLOAD_KILL_RESTART_AFTER, never).
+%%-define(OVERLOAD_KILL_RESTART_AFTER, infinity).
 
 %% The handler sends asynchronous write requests to the process
 %% controlling the i/o device, but every once in this interval
diff --git a/lib/kernel/src/logger_std_h.erl b/lib/kernel/src/logger_std_h.erl
index ce9daa50ab..a03e1ffc2a 100644
--- a/lib/kernel/src/logger_std_h.erl
+++ b/lib/kernel/src/logger_std_h.erl
@@ -28,7 +28,7 @@
 -include_lib("kernel/include/file.hrl").
 
 %% API
--export([start_link/3, info/1, sync/1, reset/1]).
+-export([start_link/3, info/1, filesync/1, reset/1]).
 
 %% gen_server and proc_lib callbacks
 -export([init/1, handle_call/3, handle_cast/2, handle_info/2,
@@ -60,19 +60,19 @@ start_link(Name, Config, HandlerState) ->
 
 %%%-----------------------------------------------------------------
 %%%
--spec sync(Name) -> ok | {error,Reason} when
+-spec filesync(Name) -> ok | {error,Reason} when
       Name :: atom(),
       Reason :: handler_busy | {badarg,term()}.
 
-sync(Name) when is_atom(Name) ->
+filesync(Name) when is_atom(Name) ->
     try
         gen_server:call(?name_to_reg_name(?MODULE,Name),
                         filesync, ?DEFAULT_CALL_TIMEOUT)
     catch
         _:{timeout,_} -> {error,handler_busy}
     end;
-sync(Name) ->
-    {error,{badarg,{sync,[Name]}}}.
+filesync(Name) ->
+    {error,{badarg,{filesync,[Name]}}}.
 
 %%%-----------------------------------------------------------------
 %%%
@@ -816,7 +816,7 @@ sync_dev(Fd, DevName, PrevSyncResult, HandlerName) ->
             %% don't report same error twice
             PrevSyncResult;
         Error ->
-            logger_h_common:error_notify({HandlerName,sync,DevName,Error}),
+            logger_h_common:error_notify({HandlerName,filesync,DevName,Error}),
             Error
     end.
 
diff --git a/lib/kernel/test/logger_SUITE.erl b/lib/kernel/test/logger_SUITE.erl
index f837c31e64..b367b4dd54 100644
--- a/lib/kernel/test/logger_SUITE.erl
+++ b/lib/kernel/test/logger_SUITE.erl
@@ -329,7 +329,7 @@ log_no_levels(_Config) ->
     ok.
 log_no_levels(cleanup,_Config) ->
     logger:remove_handler(h1),
-    logger:set_primary_config(level,info),
+    logger:set_primary_config(level,notice),
     logger:unset_module_level(?MODULE),
     ok.
 
diff --git a/lib/kernel/test/logger_disk_log_h_SUITE.erl b/lib/kernel/test/logger_disk_log_h_SUITE.erl
index 5f7b505ecb..4c6fa1b5af 100644
--- a/lib/kernel/test/logger_disk_log_h_SUITE.erl
+++ b/lib/kernel/test/logger_disk_log_h_SUITE.erl
@@ -1,3 +1,22 @@
+%%
+%% %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_disk_log_h_SUITE).
 
 -compile(export_all).
@@ -26,10 +45,6 @@
 -define(log_no(File,N), lists:concat([File,".",N])).
 -define(domain,#{domain=>[?MODULE]}).
 
--define(SYNC_REP_INT, if is_atom(?FILESYNC_REPEAT_INTERVAL) -> 5500;
-                         true -> ?FILESYNC_REPEAT_INTERVAL + 500
-                      end).
-
 suite() ->
     [{timetrap,{seconds,30}},
      {ct_hooks,[logger_test_lib]}].
@@ -50,9 +65,10 @@ end_per_group(_Group, _Config) ->
 init_per_testcase(TestHooksCase, Config) when
       TestHooksCase == write_failure;
       TestHooksCase == sync_failure ->
-    if ?TEST_HOOKS_TAB == undefined ->
+    case (fun() -> ?TEST_HOOKS_TAB == undefined end)() of
+        true ->
             {skip,"Define the TEST_HOOKS macro to run this test"};
-       true ->
+        false ->
             ct:print("********** ~w **********", [TestHooksCase]),
             Config
     end;
@@ -124,7 +140,7 @@ create_log(Config) ->
                                 formatter=>{?MODULE,self()}},
                        #{file=>LogFile1}),
     logger:notice("hello", ?domain),
-    logger_disk_log_h:sync(Name1),
+    logger_disk_log_h:filesync(Name1),
     ct:pal("Checking contents of ~p", [?log_no(LogFile1,1)]),
     try_read_file(?log_no(LogFile1,1), {ok,<<"hello\n">>}, 5000),
     
@@ -137,7 +153,7 @@ create_log(Config) ->
                                 formatter=>{?MODULE,self()}},
                        #{file=>LogFile2}),
     logger:notice("dummy", ?domain),
-    logger_disk_log_h:sync(Name2),
+    logger_disk_log_h:filesync(Name2),
     ct:pal("Checking contents of ~p", [?log_no(LogFile2,1)]),
     try_read_file(?log_no(LogFile2,1), {ok,<<"dummy\n">>}, 5000),
 
@@ -158,7 +174,7 @@ open_existing_log(Config) ->
                                 formatter=>{?MODULE,self()}},
                        #{file=>LogFile1}),
     logger:notice("one", ?domain),
-    logger_disk_log_h:sync(HName),
+    logger_disk_log_h:filesync(HName),
     ct:pal("Checking contents of ~p", [?log_no(LogFile1,1)]),
     try_read_file(?log_no(LogFile1,1), {ok,<<"one\n">>}, 5000),
     logger:notice("two", ?domain),
@@ -172,7 +188,7 @@ open_existing_log(Config) ->
                                 formatter=>{?MODULE,self()}},
                        #{file=>LogFile1}),
     logger:notice("three", ?domain),
-    logger_disk_log_h:sync(HName),
+    logger_disk_log_h:filesync(HName),
     try_read_file(?log_no(LogFile1,1), {ok,<<"one\ntwo\nthree\n">>}, 5000),
     remove_and_stop(HName),
     try_read_file(?log_no(LogFile1,1), {ok,<<"one\ntwo\nthree\n">>}, 5000).
@@ -197,22 +213,22 @@ disk_log_opts(Config) ->
     {WFileFull,wrap,{Size,2},1} = {Get(file,WInfo1),Get(type,WInfo1),
                                    Get(size,WInfo1),Get(current_file,WInfo1)},
     logger:notice("123", ?domain),
-    logger_disk_log_h:sync(WName),
+    logger_disk_log_h:filesync(WName),
     timer:sleep(500),
     1 = Get(current_file, disk_log:info(WName)),
 
     logger:notice("45", ?domain),
-    logger_disk_log_h:sync(WName),
+    logger_disk_log_h:filesync(WName),
     timer:sleep(500),
     1 = Get(current_file, disk_log:info(WName)),
 
     logger:notice("6", ?domain),
-    logger_disk_log_h:sync(WName),
+    logger_disk_log_h:filesync(WName),
     timer:sleep(500),
     2 = Get(current_file, disk_log:info(WName)),
 
     logger:notice("7890", ?domain),
-    logger_disk_log_h:sync(WName),
+    logger_disk_log_h:filesync(WName),
     timer:sleep(500),
     2 = Get(current_file, disk_log:info(WName)),
 
@@ -230,7 +246,7 @@ disk_log_opts(Config) ->
     {HFile1Full,halt,infinity} = {Get(file,HInfo1),Get(type,HInfo1),
                                   Get(size,HInfo1)},
     logger:notice("12345", ?domain),
-    logger_disk_log_h:sync(HName1),
+    logger_disk_log_h:filesync(HName1),
     timer:sleep(500),
     1 = Get(no_written_items, disk_log:info(HName1)),
 
@@ -407,8 +423,8 @@ config_fail(cleanup,_Config) ->
     logger:remove_handler(?MODULE).
 
 bad_input(_Config) ->
-    {error,{badarg,{sync,["BadType"]}}} =
-        logger_disk_log_h:sync("BadType"),
+    {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").
 
@@ -456,7 +472,7 @@ reconfig(Config) ->
                          overload_kill_enable => true,
                          overload_kill_qlen => 100000,
                          overload_kill_mem_size => 10000000,
-                         overload_kill_restart_after => never,
+                         overload_kill_restart_after => infinity,
                          filesync_repeat_interval => no_repeat},
     ok = logger:set_handler_config(?MODULE, config, HConfig1),
     #{id := ?MODULE,
@@ -469,7 +485,7 @@ reconfig(Config) ->
       overload_kill_enable := true,
       overload_kill_qlen := 100000,
       overload_kill_mem_size := 10000000,
-      overload_kill_restart_after := never,
+      overload_kill_restart_after := infinity,
       filesync_repeat_interval := no_repeat} =
         logger_disk_log_h:info(?MODULE),
 
@@ -526,7 +542,7 @@ sync(Config) ->
     logger:notice("second", ?domain),
     logger:notice("third", ?domain),
     %% do explicit sync
-    logger_disk_log_h:sync(?MODULE),
+    logger_disk_log_h:filesync(?MODULE),
     check_tracer(100),
 
     %% check that if there's no repeated disk_log_sync active,
@@ -739,9 +755,15 @@ write_failure(Config) ->
     ct:pal("LogOpts = ~p", [LogOpts = maps:get(log_opts, HState)]),
 
     ok = log_on_remote_node(Node, "Logged1"),
-    rpc:call(Node, logger_disk_log_h, sync, [?STANDARD_HANDLER]),
+    rpc:call(Node, logger_disk_log_h, filesync, [?STANDARD_HANDLER]),
     ?check_no_log,
-    try_read_file(Log, {ok,<<"Logged1\n">>}, ?SYNC_REP_INT),
+
+    SyncRepInt = case (fun() -> is_atom(?FILESYNC_REPEAT_INTERVAL) end)() of
+                     true -> 5500;
+                     false -> ?FILESYNC_REPEAT_INTERVAL + 500
+                 end,
+
+    try_read_file(Log, {ok,<<"Logged1\n">>}, SyncRepInt),
 
     rpc:call(Node, ?MODULE, set_result, [disk_log_blog,{error,no_such_log}]),
     ok = log_on_remote_node(Node, "Cause simple error printout"),
@@ -759,9 +781,9 @@ write_failure(Config) ->
 
     rpc:call(Node, ?MODULE, set_result, [disk_log_blog,ok]),
     ok = log_on_remote_node(Node, "Logged2"),
-    rpc:call(Node, logger_disk_log_h, sync, [?STANDARD_HANDLER]),
+    rpc:call(Node, logger_disk_log_h, filesync, [?STANDARD_HANDLER]),
     ?check_no_log,
-    try_read_file(Log, {ok,<<"Logged1\nLogged2\n">>}, ?SYNC_REP_INT),
+    try_read_file(Log, {ok,<<"Logged1\nLogged2\n">>}, SyncRepInt),
     ok.
 write_failure(cleanup, _Config) ->
     Nodes = nodes(),
@@ -795,7 +817,7 @@ sync_failure(Config) ->
     rpc:call(Node, ?MODULE, set_result, [disk_log_sync,{error,no_such_log}]),
     ok = log_on_remote_node(Node, "Cause simple error printout"),
     
-    ?check({error,{?STANDARD_HANDLER,sync,LogOpts,{error,no_such_log}}}),
+    ?check({error,{?STANDARD_HANDLER,filesync,LogOpts,{error,no_such_log}}}),
 
     ok = log_on_remote_node(Node, "No second error printout"),
     ?check_no_log,
@@ -803,7 +825,7 @@ sync_failure(Config) ->
     rpc:call(Node, ?MODULE, set_result,
              [disk_log_sync,{error,{blocked_log,?STANDARD_HANDLER}}]),
     ok = log_on_remote_node(Node, "Cause simple error printout"),
-    ?check({error,{?STANDARD_HANDLER,sync,LogOpts,
+    ?check({error,{?STANDARD_HANDLER,filesync,LogOpts,
                    {error,{blocked_log,?STANDARD_HANDLER}}}}),
 
     rpc:call(Node, ?MODULE, set_result, [disk_log_sync,ok]),
@@ -861,8 +883,8 @@ op_switch_to_sync(Config) ->
     ok = logger:set_handler_config(?MODULE, NewHConfig),
     send_burst({n,NumOfReqs}, seq, {chars,79}, notice),
     Lines = count_lines(Log),
-    ok = file_delete(Log),
     NumOfReqs = Lines,
+    ok = file_delete(Log),
     ok.
 op_switch_to_sync(cleanup, _Config) ->
     ok = stop_handler(?MODULE).
@@ -892,11 +914,11 @@ op_switch_to_drop(Config) ->
                     _ <- lists:seq(1, Bursts)],
                 Logged = count_lines(Log),
                 ok = stop_handler(?MODULE),
-                _ = file_delete(Log),
                 ct:pal("Number of messages dropped = ~w (~w)",
                        [Procs*NumOfReqs*Bursts-Logged,Procs*NumOfReqs*Bursts]),
                 true = (Logged < (Procs*NumOfReqs*Bursts)),
                 true = (Logged > 0),
+                _ = file_delete(Log),
                 ok
         end,
     %% As it's tricky to get the timing right in only one go, we perform the
@@ -944,11 +966,11 @@ op_switch_to_flush(Config) ->
                     _ <- lists:seq(1,Bursts)],
                 Logged = count_lines(Log),
                 ok= stop_handler(?MODULE),
-                _ = file_delete(Log),
                 ct:pal("Number of messages flushed/dropped = ~w (~w)",
                        [NumOfReqs*Procs*Bursts-Logged,NumOfReqs*Procs*Bursts]),
                 true = (Logged < (NumOfReqs*Procs*Bursts)),
                 true = (Logged > 0),
+                _ = file_delete(Log),
                 ok
         end,
     %% As it's tricky to get the timing right in only one go, we perform the
@@ -976,8 +998,9 @@ limit_burst_disabled(Config) ->
     send_burst({n,NumOfReqs}, seq, {chars,79}, notice),
     Logged = count_lines(Log),
     ct:pal("Number of messages logged = ~w", [Logged]),
+    NumOfReqs = Logged,
     ok = file_delete(Log),
-    NumOfReqs = Logged.
+    ok.
 limit_burst_disabled(cleanup, _Config) ->
     ok = stop_handler(?MODULE).
 
@@ -995,8 +1018,9 @@ limit_burst_enabled_one(Config) ->
     send_burst({n,NumOfReqs}, seq, {chars,79}, notice),
     Logged = count_lines(Log),
     ct:pal("Number of messages logged = ~w", [Logged]),
+    ReqLimit = Logged,
     ok = file_delete(Log),
-    ReqLimit = Logged.
+    ok.
 limit_burst_enabled_one(cleanup, _Config) ->
     ok = stop_handler(?MODULE).
 
@@ -1017,9 +1041,10 @@ limit_burst_enabled_period(Config) ->
     Logged = count_lines(Log),
     ct:pal("Number of messages sent = ~w~nNumber of messages logged = ~w",
            [Sent,Logged]),
-    ok = file_delete(Log),
     true = (Logged > (ReqLimit*Windows)) andalso
-           (Logged < (ReqLimit*(Windows+2))).
+           (Logged < (ReqLimit*(Windows+2))),
+    ok = file_delete(Log),
+    ok.
 limit_burst_enabled_period(cleanup, _Config) ->
     ok = stop_handler(?MODULE).
 
@@ -1119,7 +1144,7 @@ restart_after(Config) ->
     NewHConfig1 =
         HConfig#{config=>DLHConfig#{overload_kill_enable=>true,
                                     overload_kill_qlen=>10,
-                                    overload_kill_restart_after=>never}},
+                                    overload_kill_restart_after=>infinity}},
     ok = logger:set_handler_config(?MODULE, NewHConfig1),
     MRef1 = erlang:monitor(process, whereis(h_proc_name())),
     %% kill handler
@@ -1173,7 +1198,7 @@ handler_requests_under_load(Config) ->
                                       flush_qlen => 2000,
                                       burst_limit_enable => false}},
     ok = logger:set_handler_config(?MODULE, NewHConfig),
-    Pid = spawn_link(fun() -> send_requests(?MODULE, 1, [{sync,[]},
+    Pid = spawn_link(fun() -> send_requests(?MODULE, 1, [{filesync,[]},
                                                          {info,[]},
                                                          {reset,[]},
                                                          {change_config,[]}])
@@ -1220,6 +1245,8 @@ start_handler(Name, FuncName, Config) ->
     Dir = ?config(priv_dir,Config),
     File = filename:join(Dir, FuncName),
     ct:pal("Logging to ~tp", [File]),
+    FullFile = lists:concat([File,".1"]),
+    _ = file_delete(FullFile),
     ok = logger:add_handler(Name,
                             logger_disk_log_h,
                             #{config=>#{file => File,
@@ -1229,7 +1256,7 @@ start_handler(Name, FuncName, Config) ->
                               filters=>?DEFAULT_HANDLER_FILTERS([Name]),
                               formatter=>{?MODULE,op}}),
     {ok,HConfig = #{config := DLHConfig}} = logger:get_handler_config(Name),
-    {lists:concat([File,".1"]),HConfig,DLHConfig}.
+    {FullFile,HConfig,DLHConfig}.
     
 stop_handler(Name) ->
     ct:pal("Stopping handler ~p!", [Name]),
@@ -1256,7 +1283,8 @@ send_n_burst(N, seq, Text, Class) ->
     send_n_burst(N-1, seq, Text, Class);
 send_n_burst(N, {spawn,Ps,TO}, Text, Class) ->
     ct:pal("~w processes each sending ~w messages", [Ps,N]),
-    PerProc = fun() -> 
+    PerProc = fun() ->
+                      process_flag(priority,high),
                       send_n_burst(N, seq, Text, Class)
               end,
     MRefs = [begin if TO == 0 -> ok; true -> timer:sleep(TO) end,
@@ -1399,10 +1427,10 @@ wait_until_written(File, Sz) ->
         {ok,#file_info{size = Sz}} ->
             timer:sleep(1000),
             case file:read_file_info(File) of
-                {ok,#file_info{size = Sz1}} ->
+                {ok,#file_info{size = Sz}} ->
                     ok;
-                {ok,#file_info{size = Sz2}} ->
-                    wait_until_written(File, Sz2)
+                {ok,#file_info{size = Sz1}} ->
+                    wait_until_written(File, Sz1)
             end;
         {ok,#file_info{size = Sz1}} ->
             wait_until_written(File, Sz1)
diff --git a/lib/kernel/test/logger_env_var_SUITE.erl b/lib/kernel/test/logger_env_var_SUITE.erl
index 6e182d4bca..04a4364947 100644
--- a/lib/kernel/test/logger_env_var_SUITE.erl
+++ b/lib/kernel/test/logger_env_var_SUITE.erl
@@ -214,6 +214,7 @@ logger_file(Config) ->
                       file,% dest
                       0),% progress in std logger
 
+    notice = maps:get(level,P),
     #{module:=logger_std_h} = StdC = find(?STANDARD_HANDLER,Hs),
     all = maps:get(level,StdC),
     StdFilters = maps:get(filters,StdC),
@@ -525,12 +526,12 @@ logger_many_handlers_default_last_broken_filter(Config) ->
               {logger_level,info}], LogErr, LogInfo, 7).
 
 logger_many_handlers(Config, Env, LogErr, LogInfo, NumProgress) ->
-    {ok,#{handlers:=Hs},Node} = setup(Config,Env),
+    {ok,_,Node} = setup(Config,Env),
     check_single_log(Node,LogErr,
                      file,% dest
                      0,% progress in std logger
                      error), % level
-    ok = rpc:call(Node,logger_std_h,sync,[info]),
+    ok = rpc:call(Node,logger_std_h,filesync,[info]),
     {ok, Bin} = file:read_file(LogInfo),
     ct:log("Log content:~n~s",[Bin]),
     match(Bin,<<"info:">>,NumProgress,info,info),
diff --git a/lib/kernel/test/logger_formatter_SUITE.erl b/lib/kernel/test/logger_formatter_SUITE.erl
index 864a40b618..8fe8d5199b 100644
--- a/lib/kernel/test/logger_formatter_SUITE.erl
+++ b/lib/kernel/test/logger_formatter_SUITE.erl
@@ -208,7 +208,7 @@ template(_Config) ->
               time=>Time,
               tuple=>{1,atom,"list"},
               nested=>#{subkey=>subvalue}},
-    Template6 = lists:join(";",maps:keys(maps:remove(nested,Meta6)) ++
+    Template6 = lists:join(";",lists:sort(maps:keys(maps:remove(nested,Meta6))) ++
                                [[nested,subkey]]),
     String6 = format(info,{"~p",[term]},Meta6,#{template=>Template6,
                                                 single_line=>true}),
diff --git a/lib/kernel/test/logger_legacy_SUITE.erl b/lib/kernel/test/logger_legacy_SUITE.erl
index de73b6152a..c3cab07d81 100644
--- a/lib/kernel/test/logger_legacy_SUITE.erl
+++ b/lib/kernel/test/logger_legacy_SUITE.erl
@@ -20,6 +20,8 @@
 -module(logger_legacy_SUITE).
 
 -compile(export_all).
+-compile({nowarn_deprecated_function,[{gen_fsm,start,3},
+                                      {gen_fsm,send_all_state_event,2}]}).
 
 -include_lib("common_test/include/ct.hrl").
 -include_lib("kernel/include/logger.hrl").
@@ -89,6 +91,7 @@ init_per_group(_Group, Config) ->
 end_per_group(sasl, Config) ->
     Apps = ?config(stop_apps,Config),
     [application:stop(App) || App <- Apps],
+    ok = logger:set_primary_config(level,notice),
     ok;
 end_per_group(_Group, _Config) ->
     ok.
@@ -122,7 +125,7 @@ all() ->
 
 gen_server(_Config) ->
     {ok,Pid} = gen_server:start(?MODULE,gen_server,[]),
-    Msg = fun() -> a=b end,
+    Msg = fun() -> erlang:error({badmatch,b}) end,
     Pid ! Msg,
     ?check({warning_msg,"** Undefined handle_info in ~p"++_,[?MODULE,Msg]}),
     ok = gen_server:cast(Pid,Msg),
@@ -132,7 +135,7 @@ gen_server(_Config) ->
 gen_event(_Config) ->
     {ok,Pid} = gen_event:start(),
     ok = gen_event:add_handler(Pid,?MODULE,gen_event),
-    Msg = fun() -> a=b end,
+    Msg = fun() -> erlang:error({badmatch,b}) end,
     Pid ! Msg,
     ?check({warning_msg,"** Undefined handle_info in ~tp"++_,[?MODULE,Msg]}),
     gen_event:notify(Pid,Msg),
@@ -141,7 +144,7 @@ gen_event(_Config) ->
 
 gen_fsm(_Config) ->
     {ok,Pid} = gen_fsm:start(?MODULE,gen_fsm,[]),
-    Msg = fun() -> a=b end,
+    Msg = fun() -> erlang:error({badmatch,b}) end,
     Pid ! Msg,
     ?check({warning_msg,"** Undefined handle_info in ~p"++_,[?MODULE,Msg]}),
     gen_fsm:send_all_state_event(Pid,Msg),
@@ -150,7 +153,7 @@ gen_fsm(_Config) ->
 
 gen_statem(_Config) ->
     {ok,Pid} = gen_statem:start(?MODULE,gen_statem,[]),
-    Msg = fun() -> a=b end,
+    Msg = fun() -> erlang:error({badmatch,b}) end,
     Pid ! Msg,
     ?check({error,"** State machine ~tp terminating"++_,
             [Pid,{info,Msg},{mystate,gen_statem},error,{badmatch,b}|_]}).
@@ -179,7 +182,7 @@ sasl_reports(Config) ->
     ok = gen_server:cast(ChPid, fun() ->
                                         spawn_link(fun() -> receive x->ok end end)
                                 end),
-    Msg = fun() -> a=b end,
+    Msg = fun() -> erlang:error({badmatch,b}) end,
     ok = gen_server:cast(ChPid,Msg),
     ?check_no_flush({error,"** Generic server ~tp terminating"++_,
                      [ChPid,{'$gen_cast',Msg},gen_server,{{badmatch,b},_}]}),
diff --git a/lib/kernel/test/logger_simple_h_SUITE.erl b/lib/kernel/test/logger_simple_h_SUITE.erl
index e4e48b538a..79e5c057ad 100644
--- a/lib/kernel/test/logger_simple_h_SUITE.erl
+++ b/lib/kernel/test/logger_simple_h_SUITE.erl
@@ -107,15 +107,15 @@ start_stop(cleanup,_Config) ->
 replace_default(Config) ->
 
     {ok, _, Node} = logger_test_lib:setup(Config, [{logger, [{handler, default, undefined}]}]),
-    log(Node, emergency, [M1=?str]),
-    log(Node, alert, [M2=?str,[]]),
-    log(Node, error, [M3=?map_rep]),
-    log(Node, info, [M4=?keyval_rep]),
-    log(Node, info, [M41=?keyval_rep++[not_key_val]]),
-    rpc:call(Node, error_logger, error_report, [some_type,M5=?map_rep]),
-    rpc:call(Node, error_logger, warning_report, ["some_type",M6=?map_rep]),
-    log(Node, critical, [M7=?str,[A7=?keyval_rep]]),
-    log(Node, notice, [M8=["fake",string,"line:",?LINE]]),
+    log(Node, emergency, [?str]),
+    log(Node, alert, [?str,[]]),
+    log(Node, error, [?map_rep]),
+    log(Node, info, [?keyval_rep]),
+    log(Node, info, [?keyval_rep++[not_key_val]]),
+    rpc:call(Node, error_logger, error_report, [some_type,?map_rep]),
+    rpc:call(Node, error_logger, warning_report, ["some_type",?map_rep]),
+    log(Node, critical, [?str,[?keyval_rep]]),
+    log(Node, notice, [["fake",string,"line:",?LINE]]),
 
     Env = rpc:call(Node, application, get_env, [kernel, logger, []]),
     ok = rpc:call(Node, logger, add_handlers, [Env]),
@@ -127,11 +127,11 @@ replace_file(Config) ->
     {ok, _, Node} = logger_test_lib:setup(Config, [{logger, [{handler, default, undefined}]}]),
     log(Node, emergency, [M1=?str]),
     log(Node, alert, [M2=?str,[]]),
-    log(Node, error, [M3=?map_rep]),
-    log(Node, warning, [M4=?keyval_rep]),
-    log(Node, warning, [M41=?keyval_rep++[not_key_val]]),
-    log(Node, critical, [M7=?str,[A7=?keyval_rep]]),
-    log(Node, notice, [M8=["fake",string,"line:",?LINE]]),
+    log(Node, error, [?map_rep]),
+    log(Node, warning, [?keyval_rep]),
+    log(Node, warning, [?keyval_rep++[not_key_val]]),
+    log(Node, critical, [?str,[?keyval_rep]]),
+    log(Node, notice, [["fake",string,"line:",?LINE]]),
 
     File = filename:join(proplists:get_value(priv_dir,Config),
                          atom_to_list(?FUNCTION_NAME)++".log"),
@@ -171,11 +171,11 @@ replace_disk_log(Config) ->
     {ok, _, Node} = logger_test_lib:setup(Config, [{logger, [{handler, default, undefined}]}]),
     log(Node, emergency, [M1=?str]),
     log(Node, alert, [M2=?str,[]]),
-    log(Node, error, [M3=?map_rep]),
-    log(Node, warning, [M4=?keyval_rep]),
-    log(Node, warning, [M41=?keyval_rep++[not_key_val]]),
-    log(Node, critical, [M7=?str,[A7=?keyval_rep]]),
-    log(Node, notice, [M8=["fake",string,"line:",?LINE]]),
+    log(Node, error, [?map_rep]),
+    log(Node, warning, [?keyval_rep]),
+    log(Node, warning, [?keyval_rep++[not_key_val]]),
+    log(Node, critical, [?str,[?keyval_rep]]),
+    log(Node, notice, [["fake",string,"line:",?LINE]]),
 
     File = filename:join(proplists:get_value(priv_dir,Config),
                          atom_to_list(?FUNCTION_NAME)++".log"),
diff --git a/lib/kernel/test/logger_std_h_SUITE.erl b/lib/kernel/test/logger_std_h_SUITE.erl
index 36b123b07d..134358bb64 100644
--- a/lib/kernel/test/logger_std_h_SUITE.erl
+++ b/lib/kernel/test/logger_std_h_SUITE.erl
@@ -45,10 +45,6 @@
 -define(bin(Msg), list_to_binary(Msg++"\n")).
 -define(domain,#{domain=>[?MODULE]}).
 
--define(FILESYNC_REP_INT, if is_atom(?FILESYNC_REPEAT_INTERVAL) -> 5500;
-                             true -> ?FILESYNC_REPEAT_INTERVAL + 500
-                          end).
-
 suite() ->
     [{timetrap,{seconds,30}},
      {ct_hooks,[logger_test_lib]}].
@@ -73,12 +69,25 @@ end_per_group(_Group, _Config) ->
 init_per_testcase(TestHooksCase, Config) when
       TestHooksCase == write_failure;
       TestHooksCase == sync_failure ->
-    if ?TEST_HOOKS_TAB == undefined ->
+    case (fun() -> ?TEST_HOOKS_TAB == undefined end)() of
+        true ->
             {skip,"Define the TEST_HOOKS macro to run this test"};
-       true ->
+        false ->
             ct:print("********** ~w **********", [TestHooksCase]),
             Config
     end;
+init_per_testcase(OPCase, Config) when
+      OPCase == qlen_kill_new;
+      OPCase == restart_after ->
+    case re:run(erlang:system_info(system_version),
+                "dirty-schedulers-TEST",
+                [{capture,none}]) of
+        match ->
+            {skip,"Overload protection test skipped on dirty-schedulers-TEST"};
+        nomatch ->
+            ct:print("********** ~w **********", [OPCase]),
+            Config
+    end;
 init_per_testcase(TestCase, Config) ->
     ct:print("********** ~w **********", [TestCase]),
     Config.
@@ -175,13 +184,13 @@ add_remove_instance_file(Log, Type) ->
     logger:notice(M1=?msg,?domain),
     ?check(M1),
     B1 = ?bin(M1),
-    try_read_file(Log, {ok,B1}, ?FILESYNC_REP_INT),
+    try_read_file(Log, {ok,B1}, filesync_rep_int()),
     ok = logger:remove_handler(?MODULE),
     timer:sleep(500),
     undefined = whereis(h_proc_name()),
     logger:notice(?msg,?domain),
     ?check_no_log,
-    try_read_file(Log, {ok,B1}, ?FILESYNC_REP_INT),
+    try_read_file(Log, {ok,B1}, filesync_rep_int()),
     ok.
 
 default_formatter(_Config) ->
@@ -214,11 +223,17 @@ errors(Config) ->
         logger:add_handler(?MODULE,logger_std_h,
                            #{config => #{type => faulty_type}}),
 
-    NoDir = lists:concat(["/",?MODULE,"_dir"]),
-    {error,
-     {handler_not_added,{{open_failed,NoDir,eacces},_}}} =
-        logger:add_handler(myh2,logger_std_h,
-                           #{config=>#{type=>{file,NoDir}}}),
+    case os:type() of
+        {win32,_} ->
+            %% No use in testing file access on windows
+            ok;
+        _ ->
+            NoDir = lists:concat(["/",?MODULE,"_dir"]),
+            {error,
+             {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,_},_}}} =
@@ -393,7 +408,7 @@ crash_std_h(cleanup) ->
     [test_server:stop_node(Node) || Node <- Nodes].
 
 sync_and_read(Node,disk_log,Log) ->
-    rpc:call(Node,logger_disk_log_h,sync,[?STANDARD_HANDLER]),
+    rpc:call(Node,logger_disk_log_h,filesync,[?STANDARD_HANDLER]),
     case file:read_file(Log ++ ".1") of
         {ok,<<>>} ->
             timer:sleep(5000),
@@ -402,7 +417,7 @@ sync_and_read(Node,disk_log,Log) ->
             Ok
     end;
 sync_and_read(Node,file,Log) ->
-    rpc:call(Node,logger_std_h,sync,[?STANDARD_HANDLER]),
+    rpc:call(Node,logger_std_h,filesync,[?STANDARD_HANDLER]),
     case file:read_file(Log) of
         {ok,<<>>} ->
             timer:sleep(5000),
@@ -412,7 +427,7 @@ sync_and_read(Node,file,Log) ->
     end.
 
 bad_input(_Config) ->
-    {error,{badarg,{sync,["BadType"]}}} = logger_std_h:sync("BadType"),
+    {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").
 
@@ -455,7 +470,7 @@ reconfig(Config) ->
                                      overload_kill_enable => true,
                                      overload_kill_qlen => 100000,
                                      overload_kill_mem_size => 10000000,
-                                     overload_kill_restart_after => never,
+                                     overload_kill_restart_after => infinity,
                                      filesync_repeat_interval => no_repeat}),
     #{id := ?MODULE,
       type := standard_io,
@@ -469,7 +484,7 @@ reconfig(Config) ->
       overload_kill_enable := true,
       overload_kill_qlen := 100000,
       overload_kill_mem_size := 10000000,
-      overload_kill_restart_after := never,
+      overload_kill_restart_after := infinity,
       filesync_repeat_interval := no_repeat} = logger_std_h:info(?MODULE),
     ok.
 
@@ -499,7 +514,7 @@ file_opts(Config) ->
     logger:notice(M1=?msg,?domain),
     ?check(M1),
     B1 = ?bin(M1),
-    try_read_file(Log, {ok,B1}, ?FILESYNC_REP_INT),
+    try_read_file(Log, {ok,B1}, filesync_rep_int()),
     ok.
 file_opts(cleanup, _Config) ->
     logger:remove_handler(?MODULE).
@@ -526,7 +541,7 @@ sync(Config) ->
 
     logger:notice("first", ?domain),
     %% wait for automatic filesync
-    check_tracer(?FILESYNC_REP_INT*2),
+    check_tracer(filesync_rep_int()*2),
 
     %% check that explicit filesync is only done once
     start_tracer([{logger_std_h, write_to_dev, 5},
@@ -539,9 +554,9 @@ sync(Config) ->
                  ]),
     logger:notice("second", ?domain),
     %% do explicit sync
-    logger_std_h:sync(?MODULE),
+    logger_std_h:filesync(?MODULE),
     %% a second sync should be ignored
-    logger_std_h:sync(?MODULE),
+    logger_std_h:filesync(?MODULE),
     check_tracer(100),
 
     %% check that if there's no repeated filesync active,
@@ -600,9 +615,9 @@ write_failure(Config) ->
     rpc:call(Node, ?MODULE, set_result, [file_write,ok]),
 
     ok = log_on_remote_node(Node, "Logged1"),
-    rpc:call(Node, logger_std_h, sync, [?STANDARD_HANDLER]),
+    rpc:call(Node, logger_std_h, filesync, [?STANDARD_HANDLER]),
     ?check_no_log,
-    try_read_file(Log, {ok,<<"Logged1\n">>}, ?FILESYNC_REP_INT),
+    try_read_file(Log, {ok,<<"Logged1\n">>}, filesync_rep_int()),
 
     rpc:call(Node, ?MODULE, set_result, [file_write,{error,terminated}]),
     ok = log_on_remote_node(Node, "Cause simple error printout"),
@@ -618,9 +633,9 @@ write_failure(Config) ->
 
     rpc:call(Node, ?MODULE, set_result, [file_write,ok]),
     ok = log_on_remote_node(Node, "Logged2"),
-    rpc:call(Node, logger_std_h, sync, [?STANDARD_HANDLER]),
+    rpc:call(Node, logger_std_h, filesync, [?STANDARD_HANDLER]),
     ?check_no_log,
-    try_read_file(Log, {ok,<<"Logged1\nLogged2\n">>}, ?FILESYNC_REP_INT),
+    try_read_file(Log, {ok,<<"Logged1\nLogged2\n">>}, filesync_rep_int()),
     ok.
 write_failure(cleanup, _Config) ->
     Nodes = nodes(),
@@ -649,14 +664,14 @@ sync_failure(Config) ->
     rpc:call(Node, ?MODULE, set_result, [file_datasync,{error,terminated}]),
     ok = log_on_remote_node(Node, "Cause simple error printout"),
     
-    ?check({error,{?STANDARD_HANDLER,sync,Log,{error,terminated}}}),
+    ?check({error,{?STANDARD_HANDLER,filesync,Log,{error,terminated}}}),
 
     ok = log_on_remote_node(Node, "No second error printout"),
     ?check_no_log,
 
     rpc:call(Node, ?MODULE, set_result, [file_datasync,{error,eacces}]),
     ok = log_on_remote_node(Node, "Cause simple error printout"),
-    ?check({error,{?STANDARD_HANDLER,sync,Log,{error,eacces}}}),
+    ?check({error,{?STANDARD_HANDLER,filesync,Log,{error,eacces}}}),
 
     rpc:call(Node, ?MODULE, set_result, [file_datasync,ok]),
     ok = log_on_remote_node(Node, "Logged2"),
@@ -677,10 +692,10 @@ start_std_h_on_new_node(Config, Log) ->
     Node.
 
 %% functions for test hook macros to be called by rpc
-set_internal_log(Mod, Func) ->
-    ?set_internal_log({Mod,Func}).
-set_result(Op, Result) ->
-    ?set_result(Op, Result).
+set_internal_log(_Mod, _Func) ->
+    ?set_internal_log({_Mod,_Func}).
+set_result(_Op, _Result) ->
+    ?set_result(_Op, _Result).
 set_defaults() ->
     ?set_defaults().
 
@@ -707,7 +722,6 @@ op_switch_to_sync_file(Config) ->
     %%    TRecvPid = start_op_trace(),
     send_burst({n,NumOfReqs}, seq, {chars,79}, notice),
     Lines = count_lines(Log),
-    ok = file_delete(Log),
     %% true = analyse_trace(TRecvPid,
     %%                      fun(Events) -> find_mode(async,Events) end),
     %% true = analyse_trace(TRecvPid,
@@ -720,6 +734,7 @@ op_switch_to_sync_file(Config) ->
     %%                       fun(Events) -> find_mode(flush,Events) end),    
     %%    stop_op_trace(TRecvPid),
     NumOfReqs = Lines,
+    ok = file_delete(Log),
     ok.
 op_switch_to_sync_file(cleanup, _Config) ->
     ok = stop_handler(?MODULE).
@@ -764,11 +779,11 @@ op_switch_to_drop_file(Config) ->
                     _ <- lists:seq(1, Bursts)],
                 Logged = count_lines(Log),
                 ok = stop_handler(?MODULE),
-                _ = file_delete(Log),
                 ct:pal("Number of messages dropped = ~w (~w)",
                        [Procs*NumOfReqs*Bursts-Logged,Procs*NumOfReqs*Bursts]),
                 true = (Logged < (Procs*NumOfReqs*Bursts)),
                 true = (Logged > 0),
+                _ = file_delete(Log),
                 ok
         end,
     %% As it's tricky to get the timing right in only one go, we perform the
@@ -832,11 +847,11 @@ op_switch_to_flush_file(Config) ->
                     _ <- lists:seq(1,Bursts)],
                 Logged = count_lines(Log),
                 ok = stop_handler(?MODULE),
-                _ = file_delete(Log),
                 ct:pal("Number of messages flushed/dropped = ~w (~w)",
                        [NumOfReqs*Procs*Bursts-Logged,NumOfReqs*Procs*Bursts]),
                 true = (Logged < (NumOfReqs*Procs*Bursts)),
                 true = (Logged > 0),
+                _ = file_delete(Log),
                 ok
         end,
     %% As it's tricky to get the timing right in only one go, we perform the
@@ -885,8 +900,9 @@ limit_burst_disabled(Config) ->
     send_burst({n,NumOfReqs}, seq, {chars,79}, notice),
     Logged = count_lines(Log),
     ct:pal("Number of messages logged = ~w", [Logged]),
+    NumOfReqs = Logged,
     ok = file_delete(Log),
-    NumOfReqs = Logged.
+    ok.
 limit_burst_disabled(cleanup, _Config) ->
     ok = stop_handler(?MODULE).
 
@@ -904,8 +920,9 @@ limit_burst_enabled_one(Config) ->
     send_burst({n,NumOfReqs}, seq, {chars,79}, notice),
     Logged = count_lines(Log),
     ct:pal("Number of messages logged = ~w", [Logged]),
+    ReqLimit = Logged,
     ok = file_delete(Log),
-    ReqLimit = Logged.
+    ok.
 limit_burst_enabled_one(cleanup, _Config) ->
     ok = stop_handler(?MODULE).
 
@@ -926,9 +943,10 @@ limit_burst_enabled_period(Config) ->
     Logged = count_lines(Log),
     ct:pal("Number of messages sent = ~w~nNumber of messages logged = ~w",
            [Sent,Logged]),
-    ok = file_delete(Log),
     true = (Logged > (ReqLimit*Windows)) andalso
-           (Logged < (ReqLimit*(Windows+2))).
+           (Logged < (ReqLimit*(Windows+2))),
+    ok = file_delete(Log),
+    ok.
 limit_burst_enabled_period(cleanup, _Config) ->
     ok = stop_handler(?MODULE).
 
@@ -950,7 +968,7 @@ kill_disabled(cleanup, _Config) ->
     ok = stop_handler(?MODULE).
 
 qlen_kill_new(Config) ->
-    {_Log,HConfig,StdHConfig} = start_handler(?MODULE, ?FUNCTION_NAME, Config),
+    {Log,HConfig,StdHConfig} = start_handler(?MODULE, ?FUNCTION_NAME, Config),
     Pid0 = whereis(h_proc_name()),
     {_,Mem0} = process_info(Pid0, memory),
     RestartAfter = ?OVERLOAD_KILL_RESTART_AFTER,
@@ -962,7 +980,7 @@ qlen_kill_new(Config) ->
     ok = logger:set_handler_config(?MODULE, NewHConfig),
     MRef = erlang:monitor(process, Pid0),
     NumOfReqs = 100,
-    Procs = 2,
+    Procs = 4,
     send_burst({n,NumOfReqs}, {spawn,Procs,0}, {chars,79}, notice),
     %% send_burst({n,NumOfReqs}, seq, {chars,79}, notice),
     receive
@@ -973,8 +991,8 @@ qlen_kill_new(Config) ->
                 killed ->
                     ct:pal("Slow shutdown, handler process was killed!", [])
             end,
-            timer:sleep(RestartAfter + 2000),
-            true = is_pid(whereis(h_proc_name())),
+            file_delete(Log),
+            {ok,_} = wait_for_process_up(h_proc_name(), RestartAfter * 3),
             ok
     after
         5000 ->
@@ -1001,7 +1019,7 @@ qlen_kill_std(_Config) ->
     {skip,"Not done yet"}.
 
 mem_kill_new(Config) ->
-    {_Log,HConfig,StdHConfig} = start_handler(?MODULE, ?FUNCTION_NAME, Config),
+    {Log,HConfig,StdHConfig} = start_handler(?MODULE, ?FUNCTION_NAME, Config),
     Pid0 = whereis(h_proc_name()),
     {_,Mem0} = process_info(Pid0, memory),
     RestartAfter = ?OVERLOAD_KILL_RESTART_AFTER,
@@ -1013,7 +1031,7 @@ mem_kill_new(Config) ->
     ok = logger:set_handler_config(?MODULE, NewHConfig),
     MRef = erlang:monitor(process, Pid0),
     NumOfReqs = 100,
-    Procs = 2,
+    Procs = 4,
     send_burst({n,NumOfReqs}, {spawn,Procs,0}, {chars,79}, notice),
     %% send_burst({n,NumOfReqs}, seq, {chars,79}, notice),
     receive
@@ -1024,8 +1042,8 @@ mem_kill_new(Config) ->
                 killed ->
                     ct:pal("Slow shutdown, handler process was killed!", [])
             end,
-            timer:sleep(RestartAfter * 3),
-            true = is_pid(whereis(h_proc_name())),
+            file_delete(Log),
+            {ok,_} = wait_for_process_up(h_proc_name(), RestartAfter * 3),
             ok
     after
         5000 ->
@@ -1041,23 +1059,27 @@ mem_kill_new(cleanup, _Config) ->
 mem_kill_std(_Config) ->
     {skip,"Not done yet"}.
 
+restart_after() ->
+    [{timetrap,{minutes,2}}].
 restart_after(Config) ->
     {Log,HConfig,StdHConfig} = start_handler(?MODULE, ?FUNCTION_NAME, Config),
      NewHConfig1 =
         HConfig#{config=>StdHConfig#{overload_kill_enable=>true,
                                      overload_kill_qlen=>10,
-                                     overload_kill_restart_after=>never}},
+                                     overload_kill_restart_after=>infinity}},
     ok = logger:set_handler_config(?MODULE, NewHConfig1),
     MRef1 = erlang:monitor(process, whereis(h_proc_name())),
     %% kill handler
-    send_burst({n,100}, {spawn,2,0}, {chars,79}, notice),
+    send_burst({n,100}, {spawn,4,0}, {chars,79}, notice),
     receive
-        {'DOWN', MRef1, _, _, _Info1} ->
-            timer:sleep(?OVERLOAD_KILL_RESTART_AFTER + 1000),
-            undefined = whereis(h_proc_name()),
+        {'DOWN', MRef1, _, _, _Reason1} ->
+            file_delete(Log),
+            error = wait_for_process_up(h_proc_name(),?OVERLOAD_KILL_RESTART_AFTER * 3),
             ok
     after
         5000 ->
+            Info1 = logger_std_h:info(?MODULE),
+            ct:pal("Handler state = ~p", [Info1]),
             ct:fail("Handler not dead! It should not have survived this!")
     end,
     
@@ -1071,16 +1093,17 @@ restart_after(Config) ->
     Pid0 = whereis(h_proc_name()),
     MRef2 = erlang:monitor(process, Pid0),
     %% kill handler
-    send_burst({n,100}, {spawn,2,0}, {chars,79}, notice),
+    send_burst({n,100}, {spawn,4,0}, {chars,79}, notice),
     receive
-        {'DOWN', MRef2, _, _, _Info2} ->
-            timer:sleep(RestartAfter + 2000),
-            Pid1 = whereis(h_proc_name()),
-            true = is_pid(Pid1),
+        {'DOWN', MRef2, _, _, _Reason2} ->
+            file_delete(Log),
+            {ok,Pid1} = wait_for_process_up(h_proc_name(),RestartAfter * 3),
             false = (Pid1 == Pid0),
             ok
     after
         5000 ->
+            Info2 = logger_std_h:info(?MODULE),
+            ct:pal("Handler state = ~p", [Info2]),
             ct:fail("Handler not dead! It should not have survived this!")
     end,
     ok.
@@ -1101,7 +1124,7 @@ handler_requests_under_load(Config) ->
                                        flush_qlen => 2000,
                                        burst_limit_enable => false}},
     ok = logger:set_handler_config(?MODULE, NewHConfig),
-    Pid = spawn_link(fun() -> send_requests(?MODULE, 1, [{sync,[]},
+    Pid = spawn_link(fun() -> send_requests(?MODULE, 1, [{filesync,[]},
                                                          {info,[]},
                                                          {reset,[]},
                                                          {change_config,[]}])
@@ -1160,6 +1183,7 @@ start_handler(Name, FuncName, Config) ->
     Log = filename:join(Dir, lists:concat([FuncName,".log"])),
     ct:pal("Logging to ~tp", [Log]),
     Type = {file,Log},
+    _ = file_delete(Log),
     ok = logger:add_handler(Name,
                             logger_std_h,
                             #{config => #{type => Type},
@@ -1184,10 +1208,10 @@ wait_until_written(File, Sz) ->
         {ok,#file_info{size = Sz}} ->
             timer:sleep(1000),
             case file:read_file_info(File) of
-                {ok,#file_info{size = Sz1}} ->
+                {ok,#file_info{size = Sz}} ->
                     ok;
-                {ok,#file_info{size = Sz2}} ->
-                    wait_until_written(File, Sz2)
+                {ok,#file_info{size = Sz1}} ->
+                    wait_until_written(File, Sz1)
             end;
         {ok,#file_info{size = Sz1}} ->
             wait_until_written(File, Sz1)
@@ -1230,7 +1254,8 @@ send_n_burst(N, seq, Text, Class) ->
     send_n_burst(N-1, seq, Text, Class);
 send_n_burst(N, {spawn,Ps,TO}, Text, Class) ->
     ct:pal("~w processes each sending ~w messages", [Ps,N]),
-    PerProc = fun() -> 
+    PerProc = fun() ->
+                      process_flag(priority,high),
                       send_n_burst(N, seq, Text, Class)
               end,
     MRefs = [begin if TO == 0 -> ok; true -> timer:sleep(TO) end,
@@ -1300,7 +1325,7 @@ add_remove_instance_nofile(Type) ->
     logger:notice(M1=?msg,?domain),
     ?check(M1),
     %% check that sync doesn't do damage even if not relevant
-    ok = logger_std_h:sync(?MODULE),
+    ok = logger_std_h:filesync(?MODULE),
     ok = logger:remove_handler(?MODULE),
     timer:sleep(500),
     undefined = whereis(h_proc_name()),
@@ -1541,3 +1566,24 @@ h_proc_name(Name) ->
 
 file_delete(Log) ->
    file:delete(Log).
+
+wait_for_process_up(Name,T) ->
+    N = (T div 500) + 1,
+    wait_for_process_up1(Name,N).
+
+wait_for_process_up1(_Name,0) ->
+    error;
+wait_for_process_up1(Name,N) ->
+    timer:sleep(500),
+    case whereis(Name) of
+        Pid when is_pid(Pid) ->
+            {ok,Pid};
+        undefined ->
+            wait_for_process_up1(Name,N-1)
+    end.
+
+filesync_rep_int() ->
+    case (fun() -> is_atom(?FILESYNC_REPEAT_INTERVAL) end)() of
+        true  -> 5500;
+        false -> ?FILESYNC_REPEAT_INTERVAL + 500
+    end.
diff --git a/lib/kernel/test/logger_test_lib.erl b/lib/kernel/test/logger_test_lib.erl
index 9097453c10..81eb9ce5eb 100644
--- a/lib/kernel/test/logger_test_lib.erl
+++ b/lib/kernel/test/logger_test_lib.erl
@@ -52,10 +52,10 @@ log(Node, M, F, A) ->
     rpc:call(Node, M, F, A ++ [MD]).
 
 sync_and_read(Node,disk_log,Log) ->
-    rpc:call(Node,logger_disk_log_h,sync,[?STANDARD_HANDLER]),
+    rpc:call(Node,logger_disk_log_h,filesync,[?STANDARD_HANDLER]),
     file:read_file(Log ++ ".1");
 sync_and_read(Node, file,Log) ->
-    ok = rpc:call(Node,logger_std_h,sync,[?STANDARD_HANDLER]),
+    ok = rpc:call(Node,logger_std_h,filesync,[?STANDARD_HANDLER]),
     file:read_file(Log).