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authorSverker Eriksson <[email protected]>2018-01-11 20:52:27 +0100
committerSverker Eriksson <[email protected]>2018-01-29 18:24:23 +0100
commit0359cdc8552ad056e976a8c097624b4305ef6755 (patch)
treef7dc7c928559e6c2d39607529b1d2b9b81dd9f4e /lib
parent919ef5de2858e606d4a9be3e0e995b0802c76e33 (diff)
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runtime_tools: Add scheduler module
Diffstat (limited to 'lib')
-rw-r--r--lib/runtime_tools/doc/src/Makefile8
-rw-r--r--lib/runtime_tools/doc/src/ref_man.xml1
-rw-r--r--lib/runtime_tools/doc/src/scheduler.xml135
-rw-r--r--lib/runtime_tools/doc/src/specs.xml1
-rw-r--r--lib/runtime_tools/src/Makefile1
-rw-r--r--lib/runtime_tools/src/runtime_tools.app.src1
-rw-r--r--lib/runtime_tools/src/scheduler.erl152
-rw-r--r--lib/runtime_tools/test/Makefile1
-rw-r--r--lib/runtime_tools/test/scheduler_SUITE.erl104
9 files changed, 403 insertions, 1 deletions
diff --git a/lib/runtime_tools/doc/src/Makefile b/lib/runtime_tools/doc/src/Makefile
index 5ce40bb995..83375d4525 100644
--- a/lib/runtime_tools/doc/src/Makefile
+++ b/lib/runtime_tools/doc/src/Makefile
@@ -41,7 +41,13 @@ RELSYSDIR = $(RELEASE_PATH)/lib/$(APPLICATION)-$(VSN)
# Target Specs
# ----------------------------------------------------
XML_APPLICATION_FILES = ref_man.xml
-XML_REF3_FILES = dbg.xml dyntrace.xml erts_alloc_config.xml system_information.xml msacc.xml
+XML_REF3_FILES = \
+ dbg.xml \
+ dyntrace.xml \
+ erts_alloc_config.xml \
+ system_information.xml \
+ msacc.xml \
+ scheduler.xml
XML_REF6_FILES = runtime_tools_app.xml
XML_PART_FILES = part_notes.xml part_notes_history.xml part.xml
diff --git a/lib/runtime_tools/doc/src/ref_man.xml b/lib/runtime_tools/doc/src/ref_man.xml
index d2fb7a29af..eb3a6f0f5c 100644
--- a/lib/runtime_tools/doc/src/ref_man.xml
+++ b/lib/runtime_tools/doc/src/ref_man.xml
@@ -37,6 +37,7 @@
<xi:include href="dyntrace.xml"/>
<xi:include href="erts_alloc_config.xml"/>
<xi:include href="msacc.xml"/>
+ <xi:include href="scheduler.xml"/>
<xi:include href="system_information.xml"/>
</application>
diff --git a/lib/runtime_tools/doc/src/scheduler.xml b/lib/runtime_tools/doc/src/scheduler.xml
new file mode 100644
index 0000000000..dd8bf73bae
--- /dev/null
+++ b/lib/runtime_tools/doc/src/scheduler.xml
@@ -0,0 +1,135 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<!DOCTYPE erlref SYSTEM "erlref.dtd">
+
+<erlref>
+ <header>
+ <copyright>
+ <year>2018</year>
+ <holder>Ericsson AB. All Rights Reserved.</holder>
+ </copyright>
+ <legalnotice>
+ 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.
+
+ </legalnotice>
+
+ <title></title>
+ <prepared></prepared>
+ <responsible></responsible>
+ <docno>1</docno>
+ <approved></approved>
+ <checked></checked>
+ <date></date>
+ <rev></rev>
+ <file>scheduler.xml</file>
+ </header>
+ <module>scheduler</module>
+ <modulesummary>Measure scheduler utilization</modulesummary>
+ <description>
+ <p>This module contains utility functions for easier measurement and
+ calculation of scheduler utilization, otherwise obtained from calling the
+ more primitive <seealso marker="erts:erlang#statistics_scheduler_wall_time">
+ <c>statistics(scheduler_wall_time)</c></seealso>.</p>
+ <p>The simplest usage is to call <seealso marker="#utilization-1">
+ <c>scheduler:utilization(Seconds)</c></seealso>.</p>
+ </description>
+
+ <datatypes>
+ <datatype>
+ <name name="sched_sample"/>
+ </datatype>
+ <datatype>
+ <name name="sched_type"/>
+ </datatype>
+ <datatype>
+ <name name="sched_id"/>
+ </datatype>
+ <datatype>
+ <name name="sched_util_result"/>
+ <desc>
+ <p>A list of tuples containing results for individual schedulers
+ as well as aggregated averages. <c>Util</c> is the scheduler utilization
+ as a floating point value between 0.0 and 1.0. <c>Percent</c> is the
+ same utilization as a more human readable string expressed in percent.</p>
+ <taglist>
+ <tag><c>{normal, SchedulerId, Util, Percent}</c></tag>
+ <item>Scheduler utilization of a normal scheduler with number
+ <c>SchedulerId</c>.</item>
+ <tag><c>{cpu, SchedulerId, Util, Percent}</c></tag>
+ <item>Scheduler utilization of a dirty-cpu scheduler with number
+ <c>SchedulerId</c>.</item>
+ <tag><c>{io, SchedulerId, Util, Percent}</c></tag>
+ <item>Scheduler utilization of a dirty-io scheduler with number
+ <c>SchedulerId</c>. This tuple will only exist if both samples were
+ taken with <seealso marker="#sample_all-0"><c>sample_all/0</c></seealso>.</item>
+ <tag><c>{total, Util, Percent}</c></tag>
+ <item>Total utilization of all normal and dirty-cpu schedulers.</item>
+ <tag><c>{weighted, Util, Percent}</c></tag>
+ <item>Total utilization of all normal and dirty-cpu schedulers,
+ weighted against maximum amount of available CPU time.</item>
+ </taglist>
+ </desc>
+ </datatype>
+ </datatypes>
+
+ <funcs>
+
+ <func>
+ <name name="sample" arity="0"/>
+ <fsummary>Get scheduler utilization sample.</fsummary>
+ <desc>
+ <p>Return a scheduler utilization sample for normal and dirty-cpu
+ schedulers.</p>
+ </desc>
+ </func>
+
+ <func>
+ <name name="sample_all" arity="0"/>
+ <fsummary>Get scheduler utilization sample.</fsummary>
+ <desc>
+ <p>Return a scheduler utilization sample for all schedulers,
+ including dirty-io schedulers.</p>
+ </desc>
+ </func>
+
+ <func>
+ <name name="utilization" arity="1" clause_i="1"/>
+ <fsummary>Measure scheduler utilizations during a period of time.</fsummary>
+ <desc>
+ <p>Measure utilization for normal and dirty-cpu schedulers during
+ <c><anno>Seconds</anno></c> seconds, and then return the result.</p>
+ </desc>
+ </func>
+
+ <func>
+ <name name="utilization" arity="1" clause_i="2"/>
+ <fsummary>Measure scheduler utilizations since sample.</fsummary>
+ <desc>
+ <p>Calculate scheduler utilizations for the time interval from when
+ <c><anno>Sample</anno></c> was taken and "now". The same as calling
+ <c>scheduler:utilization(Sample, scheduler:sample_all())</c>.</p>
+ </desc>
+ </func>
+
+ <func>
+ <name name="utilization" arity="2"/>
+ <fsummary>Measure scheduler utilizations between two samples.</fsummary>
+ <desc>
+ <p>Calculates scheduler utilizations for the time interval between
+ the two samples obtained from calling
+ <seealso marker="#sample-0"><c>sample/0</c></seealso> or
+ <seealso marker="#sample_all-0"><c>sample_all/0</c></seealso>.</p>
+ </desc>
+ </func>
+
+ </funcs>
+ </erlref>
diff --git a/lib/runtime_tools/doc/src/specs.xml b/lib/runtime_tools/doc/src/specs.xml
index 978bd39e55..33fe7fa370 100644
--- a/lib/runtime_tools/doc/src/specs.xml
+++ b/lib/runtime_tools/doc/src/specs.xml
@@ -2,4 +2,5 @@
<specs xmlns:xi="http://www.w3.org/2001/XInclude">
<xi:include href="../specs/specs_system_information.xml"/>
<xi:include href="../specs/specs_msacc.xml"/>
+ <xi:include href="../specs/specs_scheduler.xml"/>
</specs>
diff --git a/lib/runtime_tools/src/Makefile b/lib/runtime_tools/src/Makefile
index 5a99c6e240..6faa9c2e35 100644
--- a/lib/runtime_tools/src/Makefile
+++ b/lib/runtime_tools/src/Makefile
@@ -45,6 +45,7 @@ MODULES= \
system_information \
observer_backend \
ttb_autostart\
+ scheduler\
msacc
HRL_FILES= ../include/observer_backend.hrl
diff --git a/lib/runtime_tools/src/runtime_tools.app.src b/lib/runtime_tools/src/runtime_tools.app.src
index 449532e5c4..09a9b447c2 100644
--- a/lib/runtime_tools/src/runtime_tools.app.src
+++ b/lib/runtime_tools/src/runtime_tools.app.src
@@ -23,6 +23,7 @@
{modules, [appmon_info, dbg,observer_backend,runtime_tools,
runtime_tools_sup,erts_alloc_config,
ttb_autostart,dyntrace,system_information,
+ scheduler,
msacc]},
{registered, [runtime_tools_sup]},
{applications, [kernel, stdlib]},
diff --git a/lib/runtime_tools/src/scheduler.erl b/lib/runtime_tools/src/scheduler.erl
new file mode 100644
index 0000000000..c896b671ac
--- /dev/null
+++ b/lib/runtime_tools/src/scheduler.erl
@@ -0,0 +1,152 @@
+%%
+%% %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%
+%%
+
+%% @doc Utility functions for easier measurement of scheduler utilization
+%% using erlang:statistics(scheduler_wall_time).
+
+-module(scheduler).
+
+-export([sample/0,
+ sample_all/0,
+ utilization/1,
+ utilization/2]).
+
+-export_type([sched_sample/0]).
+
+
+-opaque sched_sample() ::
+ {scheduler_wall_time | scheduler_wall_time_all,
+ [{sched_type(), sched_id(), ActiveTime::integer(), TotalTime::integer()}]}.
+
+-type sched_type() :: normal | cpu | io.
+
+-type sched_id() :: integer().
+
+-spec sample() -> sched_sample().
+sample() ->
+ sample(scheduler_wall_time).
+
+-spec sample_all() -> sched_sample().
+sample_all() ->
+ sample(scheduler_wall_time_all).
+
+sample(Stats) ->
+ case erlang:statistics(Stats) of
+ undefined ->
+ erlang:system_flag(scheduler_wall_time, true),
+ sample(Stats);
+
+ List ->
+ Sorted = lists:sort(List),
+ Tagged = lists:map(fun({I, A, T}) -> {sched_tag(I), I, A, T} end,
+ Sorted),
+ {Stats, Tagged}
+ end.
+
+-type sched_util_result() ::
+ [{sched_type(), sched_id(), float(), string()} |
+ {total, float(), string()} |
+ {weighted, float(), string()}].
+
+-spec utilization(Seconds) -> sched_util_result() when
+ Seconds :: pos_integer();
+ (Sample) -> sched_util_result() when
+ Sample :: sched_sample().
+utilization(Seconds) when is_integer(Seconds), Seconds > 0 ->
+ OldFlag = erlang:system_flag(scheduler_wall_time, true),
+ T0 = sample(),
+ receive after Seconds*1000 -> ok end,
+ T1 = sample(),
+ case OldFlag of
+ false ->
+ erlang:system_flag(scheduler_wall_time, OldFlag);
+ true ->
+ ok
+ end,
+ utilization(T0,T1);
+
+utilization({Stats, _}=T0) when Stats =:= scheduler_wall_time;
+ Stats =:= scheduler_wall_time_all ->
+ utilization(T0, sample(Stats)).
+
+-spec utilization(Sample1, Sample2) -> sched_util_result() when
+ Sample1 :: sched_sample(),
+ Sample2 :: sched_sample().
+utilization({Stats, Ts0}, {Stats, Ts1}) ->
+ Diffs = lists:map(fun({{Tag, I, A0, T0}, {Tag, I, A1, T1}}) ->
+ {Tag, I, (A1 - A0), (T1 - T0)}
+ end,
+ lists:zip(Ts0,Ts1)),
+
+ {Lst0, {A, T, N}} = lists:foldl(fun({Tag, I, Adiff, Tdiff}, {Lst, Acc}) ->
+ R = safe_div(Adiff, Tdiff),
+ {[{Tag, I, R, percent(R)} | Lst],
+ acc(Tag, Adiff, Tdiff, Acc)}
+ end,
+ {[], {0, 0, 0}},
+ Diffs),
+
+ Total = safe_div(A, T),
+ Lst1 = lists:reverse(Lst0),
+ Lst2 = case erlang:system_info(logical_processors_available) of
+ unknown -> Lst1;
+ LPA ->
+ Weighted = Total * (N / LPA),
+ [{weighted, Weighted, percent(Weighted)} | Lst1]
+ end,
+ [{total, Total, percent(Total)} | Lst2];
+
+utilization({scheduler_wall_time, _}=T0,
+ {scheduler_wall_time_all, Ts1}) ->
+ utilization(T0, {scheduler_wall_time, remove_io(Ts1)});
+
+utilization({scheduler_wall_time_all, Ts0},
+ {scheduler_wall_time, _}=T1) ->
+ utilization({scheduler_wall_time, remove_io(Ts0)}, T1).
+
+%% Do not include dirty-io in totals
+acc(io, _, _, Acc) ->
+ Acc;
+acc(Tag, Adiff, Tdiff, {Asum, Tsum, N}) when Tag =:= normal; Tag =:= cpu ->
+ {Adiff+Asum, Tdiff+Tsum, N+1}.
+
+
+remove_io(Ts) ->
+ lists:filter(fun({io,_,_,_}) -> false;
+ (_) -> true end,
+ Ts).
+
+safe_div(A, B) ->
+ if B == 0.0 -> 0.0;
+ true -> A / B
+ end.
+
+sched_tag(Nr) ->
+ Normal = erlang:system_info(schedulers),
+ Cpu = Normal + erlang:system_info(dirty_cpu_schedulers),
+ case Nr of
+ _ when Nr =< Normal -> normal;
+ _ when Nr =< Cpu -> cpu;
+ _ -> io
+ end.
+
+
+percent(F) ->
+ float_to_list(F*100, [{decimals,1}]) ++ [$%].
diff --git a/lib/runtime_tools/test/Makefile b/lib/runtime_tools/test/Makefile
index 61377ea09e..de37b2570d 100644
--- a/lib/runtime_tools/test/Makefile
+++ b/lib/runtime_tools/test/Makefile
@@ -9,6 +9,7 @@ MODULES = \
system_information_SUITE \
dbg_SUITE \
erts_alloc_config_SUITE \
+ scheduler_SUITE \
msacc_SUITE
ERL_FILES= $(MODULES:%=%.erl)
diff --git a/lib/runtime_tools/test/scheduler_SUITE.erl b/lib/runtime_tools/test/scheduler_SUITE.erl
new file mode 100644
index 0000000000..1c80253371
--- /dev/null
+++ b/lib/runtime_tools/test/scheduler_SUITE.erl
@@ -0,0 +1,104 @@
+%% %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(scheduler_SUITE).
+
+-export([suite/0, all/0]).
+
+%% Test cases
+-export([basic/1]).
+
+all() -> [basic].
+
+
+suite() -> [{ct_hooks,[ts_install_cth]}].
+
+
+basic(_Config) ->
+ S1 = scheduler:sample(),
+ S2 = scheduler:sample_all(),
+
+ check(scheduler:utilization(1)),
+
+ check(scheduler:utilization(S1)),
+ check(scheduler:utilization(S2)),
+ check(scheduler:utilization(S1, scheduler:sample())),
+ check(scheduler:utilization(S2, scheduler:sample())),
+
+ S3 = scheduler:sample_all(),
+ U13 = scheduler:utilization(S1, S3),
+ U13 = scheduler:utilization(S1, remove_io(S3)),
+ check(U13),
+
+ U23all = scheduler:utilization(S2, S3),
+ check(U23all),
+ U23 = scheduler:utilization(S2, remove_io(S3)),
+ U23 = scheduler:utilization(remove_io(S2), S3),
+ U23 = remove_io(U23all),
+ check(U23),
+
+ ok.
+
+
+check([{total, Tf, Ts} | List]=U) ->
+ io:format("\nU = ~p\n", [U]),
+ check_values(Tf, Ts, true),
+
+ SchdList = case hd(List) of
+ {weighted, Wf, Ws} ->
+ check_values(Wf, Ws, false),
+ tl(List);
+ _ ->
+ unknown = erlang:system_info(logical_processors_available),
+ List
+ end,
+
+ lists:foreach(fun({Type, Id, F, S}) when ((Type =:= normal) or (Type =:= cpu) or (Type =:= io)),
+ is_integer(Id) ->
+ check_values(F, S, true)
+ end,
+ SchdList),
+ ok.
+
+check_values(F, S, Max100) ->
+ true = is_float(F),
+ true = F >= 0.0,
+
+ $% = lists:last(S),
+ Sf = list_to_float(lists:droplast(S)),
+ true = Sf >= 0.0,
+ true = case Max100 of
+ true ->
+ true = F =< 1.0,
+ true = Sf =< 100.0;
+ false ->
+ true
+ end,
+ MaxDiff = 0.055555555555555555, %% change to 0.05 when float_to_list/2 is fixed
+ true = abs(F*100 - Sf) =< MaxDiff,
+ ok.
+
+
+remove_io({scheduler_wall_time_all,Lst}) ->
+ {scheduler_wall_time, remove_io(Lst)};
+remove_io(Lst) ->
+ lists:filter(fun({io,_,_,_}) -> false;
+ (_) -> true end,
+ Lst).