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authorJohn Högberg <[email protected]>2017-07-06 12:30:45 +0200
committerJohn Högberg <[email protected]>2017-07-06 12:30:45 +0200
commit5a537ae41c2295f7f19e4e01fe90acc7585f5b30 (patch)
tree7a27a822fa0e7a09e2259a77683ca4f2632df0b3 /lib/tools
parent5e0019ebb29a9fd88e0b04f0bd0b0d722e3f189e (diff)
parent876ecc058d0d7dd48f8c5f7ddaf189d278e69925 (diff)
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Merge branch 'john/erts/runtime-lcnt' into maint
* john/erts/runtime-lcnt: Document rt_mask and add warnings about copy_save Add an emulator test suite for lock counting Break erts_debug:lock_counters/1 into separate BIFs Allow toggling lock counting at runtime Move lock flags to a common header Enable register_SUITE for lcnt builds Enable lcnt smoke test on all builds that have lcnt enabled Make lock counter info independent of the locks being counted OTP-14412 OTP-13170 OTP-14413
Diffstat (limited to 'lib/tools')
-rw-r--r--lib/tools/doc/src/lcnt.xml104
-rw-r--r--lib/tools/doc/src/lcnt_chapter.xml9
-rw-r--r--lib/tools/src/lcnt.erl77
-rw-r--r--lib/tools/src/tools.app.src2
-rw-r--r--lib/tools/test/lcnt_SUITE.erl5
5 files changed, 151 insertions, 46 deletions
diff --git a/lib/tools/doc/src/lcnt.xml b/lib/tools/doc/src/lcnt.xml
index 31e5c241e9..922c2ac0f4 100644
--- a/lib/tools/doc/src/lcnt.xml
+++ b/lib/tools/doc/src/lcnt.xml
@@ -109,14 +109,6 @@
statistics. If the server held any lock statistics data before the collect then
that data is lost.
</p>
- <note>
- <p>
- When collection occurs the runtime system transitions to a single thread,
- blocking all other threads. No other tasks will be scheduled during this
- operation. Depending on the size of the data this might take a long time
- (several seconds) and cause timeouts in the system.
- </p>
- </note>
</desc>
</func>
@@ -322,24 +314,22 @@
<func>
<name>apply(Fun) -> term()</name>
<fsummary>Same as <c>apply(Fun, [])</c>.</fsummary>
+ <type>
+ <v>Fun = fun()</v>
+ </type>
<desc>
<p>Same as <c>apply(Fun, [])</c>.</p>
</desc>
</func>
<func>
<name>apply(Fun, Args) -> term()</name>
- <fsummary>Clears counters, applies function and collects the profiling results.</fsummary>
+ <fsummary>Same as <c>apply(Module, Function, Args)</c>.</fsummary>
<type>
<v>Fun = fun()</v>
<v>Args = [term()]</v>
</type>
<desc>
- <p> Clears the lock counters and then setups the instrumentation to save all destroyed locks.
- After setup the fun is called, passing the elements in <c>Args</c> as arguments.
- When the fun returns the statistics are immediately collected to the server. After the
- collection the instrumentation is returned to its previous behavior.
- The result of the applied fun is returned.
- </p>
+ <p>Same as <c>apply(Module, Function, Args)</c>.</p>
</desc>
</func>
<func>
@@ -357,6 +347,13 @@
collection the instrumentation is returned to its previous behavior.
The result of the applied function is returned.
</p>
+ <warning>
+ <p>
+ This function should only be used for micro-benchmarks; it sets <c>copy_save</c>
+ to <c>true</c> for the duration of the call, which can quickly lead to running
+ out of memory.
+ </p>
+ </warning>
</desc>
</func>
@@ -429,6 +426,68 @@
<desc> <p>Clear the internal counters. Same as <c>lcnt:clear(Node)</c>.</p></desc>
</func>
+ <func>
+ <name>rt_mask() -> [category_atom()]</name>
+ <fsummary>Same as <c>rt_mask(node())</c>.</fsummary>
+ <desc><p>Same as <c>rt_mask(node())</c>.</p></desc>
+ </func>
+
+ <func>
+ <name>rt_mask(Node) -> [category_atom()]</name>
+ <fsummary>Returns the current lock category mask.</fsummary>
+ <type>
+ <v>Node = node()</v>
+ </type>
+ <desc>
+ <p>
+ Refer to <c>rt_mask/2</c> for a list of valid categories. All
+ categories are enabled by default.
+ </p>
+ </desc>
+ </func>
+
+ <func>
+ <name>rt_mask(Categories) -> ok | {error, copy_save_enabled}</name>
+ <fsummary>Same as <c>rt_mask(node(), Categories)</c>.</fsummary>
+ <type>
+ <v>Categories = [atom()]</v>
+ </type>
+ <desc><p>Same as <c>rt_mask(node(), Categories)</c>.</p></desc>
+ </func>
+
+ <func>
+ <name>rt_mask(Node, Categories) -> ok | {error, copy_save_enabled}</name>
+ <fsummary>Changes the lock category mask.</fsummary>
+ <type>
+ <v>Node = node()</v>
+ <v>Categories = [atom()]</v>
+ </type>
+ <desc>
+ <p>
+ Sets the lock category mask to the given categories.
+ </p>
+ <p>
+ This will fail if the <c>copy_save</c> option is enabled; see
+ <c>lcnt:rt_opt/2</c>.
+ </p>
+ <p>Valid categories are:</p>
+ <taglist>
+ <item><c>allocator</c></item>
+ <item><c>db</c> (ETS tables)</item>
+ <item><c>debug</c></item>
+ <item><c>distribution</c></item>
+ <item><c>generic</c></item>
+ <item><c>io</c></item>
+ <item><c>process</c></item>
+ <item><c>scheduler</c></item>
+ </taglist>
+ <p>
+ This list is subject to change at any time, as is the category any given lock
+ may belong to.
+ </p>
+ </desc>
+ </func>
+
<func>
<name>rt_opt({Type, bool()}) -> bool()</name>
<fsummary>Same as <c>rt_opt(node(), {Type, Opt})</c>.</fsummary>
@@ -442,16 +501,25 @@
<v>Type = copy_save | process_locks</v>
</type>
<desc>
- <p>Changes the lock counter behavior and returns the previous behaviour.</p>
<p>Option description:</p>
<taglist>
<tag><c>{copy_save, bool()}</c></tag>
- <item>Enable statistics saving from destroyed locks by copying. This might consume a lot of memory.
+ <item>Retains the statistics of destroyed locks.
<br/>Default: <c>false</c>
+ <warning>
+ <p>
+ This option will use a lot of memory when enabled, which must be
+ reclaimed with <c>lcnt:rt_clear</c>. Note that it makes no distinction
+ between locks that were destroyed and locks for which counting was
+ disabled, so enabling this option will disable changes to the lock
+ category mask.
+ </p>
+ </warning>
</item>
<tag><c>{process_locks, bool()}</c></tag>
- <item>Profile process locks.
+ <item>Profile process locks, equal to adding <c>process</c> to the lock category mask;
+ see <c>lcnt:rt_mask/2</c>
<br/>Default: <c>true</c>
</item>
</taglist>
diff --git a/lib/tools/doc/src/lcnt_chapter.xml b/lib/tools/doc/src/lcnt_chapter.xml
index c73fcb31e0..24b58136aa 100644
--- a/lib/tools/doc/src/lcnt_chapter.xml
+++ b/lib/tools/doc/src/lcnt_chapter.xml
@@ -29,7 +29,7 @@
<approved>nobody</approved>
<checked>no</checked>
<date>2009-11-26</date>
- <rev>PA1</rev>
+ <rev>PA2</rev>
<file>lcnt_chapter.xml</file>
</header>
<p>
@@ -97,8 +97,11 @@ ok
ok
</pre>
<p>
- Another way to to profile a specific function is to use <c>lcnt:apply/3</c> or <c>lcnt:apply/1</c> which does <c>lcnt:clear/0</c> before the function and <c>lcnt:collect/0</c> after its invocation.
- It also sets <c>copy_save</c> to <c>true</c> for the duration of the function call
+ Another way to to profile a specific function is to use <c>lcnt:apply/3</c> or <c>lcnt:apply/1</c>
+ which does <c>lcnt:clear/0</c> before the function and <c>lcnt:collect/0</c> after its invocation.
+ This method should only be used in micro-benchmarks since it sets <c>copy_save</c> to <c>true</c>
+ for the duration of the function call, which may cause the emulator to run out of memory if
+ attempted under load.
</p>
<pre>
Erlang R13B03 (erts-5.7.4) [source] [smp:8:8] [rq:8] [async-threads:0] [hipe]
diff --git a/lib/tools/src/lcnt.erl b/lib/tools/src/lcnt.erl
index d881fedbd5..139b3d8a4a 100644
--- a/lib/tools/src/lcnt.erl
+++ b/lib/tools/src/lcnt.erl
@@ -34,8 +34,11 @@
-export([start/0,
stop/0]).
-%% erts_debug:lock_counters api
--export([rt_collect/0,
+%% erts_debug:lcnt_xxx api
+-export([rt_mask/0,
+ rt_mask/1,
+ rt_mask/2,
+ rt_collect/0,
rt_collect/1,
rt_clear/0,
rt_clear/1,
@@ -134,27 +137,61 @@ start_internal() ->
%% -------------------------------------------------------------------- %%
%%
-%% API erts_debug:lock_counters
+%% API erts_debug:lcnt_xxx
%%
%% -------------------------------------------------------------------- %%
-rt_collect() ->
- erts_debug:lock_counters(info).
+rt_mask(Node, Categories) when is_atom(Node), is_list(Categories) ->
+ rpc:call(Node, lcnt, rt_mask, [Categories]).
+
+rt_mask(Node) when is_atom(Node) ->
+ rpc:call(Node, lcnt, rt_mask, []);
+
+rt_mask(Categories) when is_list(Categories) ->
+ case erts_debug:lcnt_control(copy_save) of
+ false ->
+ erts_debug:lcnt_control(mask, Categories);
+ true ->
+ {error, copy_save_enabled}
+ end.
+
+rt_mask() ->
+ erts_debug:lcnt_control(mask).
rt_collect(Node) ->
- rpc:call(Node, erts_debug, lock_counters, [info]).
+ rpc:call(Node, lcnt, rt_collect, []).
+rt_collect() ->
+ erts_debug:lcnt_collect().
+rt_clear(Node) ->
+ rpc:call(Node, lcnt, rt_clear, []).
rt_clear() ->
- erts_debug:lock_counters(clear).
+ erts_debug:lcnt_clear().
-rt_clear(Node) ->
- rpc:call(Node, erts_debug, lock_counters, [clear]).
+rt_opt(Node, Arg) ->
+ rpc:call(Node, lcnt, rt_opt, [Arg]).
-rt_opt({Type, Opt}) ->
- erts_debug:lock_counters({Type, Opt}).
+%% Compatibility shims for the "process/port_locks" options mentioned in the
+%% manual.
+rt_opt({process_locks, Enable}) ->
+ toggle_category(process, Enable);
+rt_opt({port_locks, Enable}) ->
+ toggle_category(io, Enable);
-rt_opt(Node, {Type, Opt}) ->
- rpc:call(Node, erts_debug, lock_counters, [{Type, Opt}]).
+rt_opt({Type, NewVal}) ->
+ PreviousVal = erts_debug:lcnt_control(Type),
+ erts_debug:lcnt_control(Type, NewVal),
+ PreviousVal.
+
+toggle_category(Category, true) ->
+ PreviousMask = erts_debug:lcnt_control(mask),
+ erts_debug:lcnt_control(mask, [Category | PreviousMask]),
+ lists:member(Category, PreviousMask);
+
+toggle_category(Category, false) ->
+ PreviousMask = erts_debug:lcnt_control(mask),
+ erts_debug:lcnt_control(mask, lists:delete(Category, PreviousMask)),
+ lists:member(Category, PreviousMask).
%% -------------------------------------------------------------------- %%
%%
@@ -192,13 +229,9 @@ call(Msg) -> gen_server:call(?MODULE, Msg, infinity).
%% -------------------------------------------------------------------- %%
apply(M,F,As) when is_atom(M), is_atom(F), is_list(As) ->
- ok = start_internal(),
- Opt = lcnt:rt_opt({copy_save, true}),
- lcnt:clear(),
- Res = erlang:apply(M,F,As),
- lcnt:collect(),
- lcnt:rt_opt({copy_save, Opt}),
- Res.
+ apply(fun() ->
+ erlang:apply(M,F,As)
+ end).
apply(Fun) when is_function(Fun) ->
lcnt:apply(Fun, []).
@@ -209,7 +242,9 @@ apply(Fun, As) when is_function(Fun) ->
lcnt:clear(),
Res = erlang:apply(Fun, As),
lcnt:collect(),
- lcnt:rt_opt({copy_save, Opt}),
+ %% _ is bound to silence a dialyzer warning; it used to fail silently and
+ %% we don't want to change the error semantics.
+ _ = lcnt:rt_opt({copy_save, Opt}),
Res.
all_conflicts() -> all_conflicts(time).
diff --git a/lib/tools/src/tools.app.src b/lib/tools/src/tools.app.src
index 12f0cfd2df..8beef49bf9 100644
--- a/lib/tools/src/tools.app.src
+++ b/lib/tools/src/tools.app.src
@@ -41,6 +41,6 @@
]
},
{runtime_dependencies, ["stdlib-3.1","runtime_tools-1.8.14",
- "kernel-3.0","erts-7.0","compiler-5.0"]}
+ "kernel-5.4","erts-9.1","compiler-5.0"]}
]
}.
diff --git a/lib/tools/test/lcnt_SUITE.erl b/lib/tools/test/lcnt_SUITE.erl
index af3ce88fdd..146c915087 100644
--- a/lib/tools/test/lcnt_SUITE.erl
+++ b/lib/tools/test/lcnt_SUITE.erl
@@ -151,10 +151,9 @@ t_swap_keys_file([File|Files]) ->
%% Simple smoke test of actual lock-counting, if running on
%% a run-time with lock-counting enabled.
-
smoke_lcnt(Config) ->
- case erlang:system_info(build_type) of
- lcnt ->
+ case catch erlang:system_info(lock_counting) of
+ true ->
do_smoke_lcnt(Config);
_ ->
{skip,"Lock counting is not enabled"}