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authorRickard Green <[email protected]>2017-05-18 20:42:04 +0200
committerRickard Green <[email protected]>2017-05-19 13:10:59 +0200
commit32ea8ba368c455afba07afd85bed6fb57879f56d (patch)
treedee24e857c59b7298a020315dbf81c793553bdd6 /erts/doc
parent773c4d4f0416f25e3c0c6939f8d0871dc4486bab (diff)
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Make statistics/1 aware of dirty run-queues and tasks
Diffstat (limited to 'erts/doc')
-rw-r--r--erts/doc/src/erlang.xml189
1 files changed, 128 insertions, 61 deletions
diff --git a/erts/doc/src/erlang.xml b/erts/doc/src/erlang.xml
index 6f70ae4a52..e93e9a2658 100644
--- a/erts/doc/src/erlang.xml
+++ b/erts/doc/src/erlang.xml
@@ -6124,28 +6124,60 @@ true</pre>
<fsummary>Information about active processes and ports.</fsummary>
<desc>
<marker id="statistics_active_tasks"></marker>
+ <p>Returns the same as
+ <seealso marker="#statistics_active_tasks_all">
+ <c>statistics(active_tasks_all)</c></seealso>
+ with the exception that no information about the dirty
+ IO run queue and its associated schedulers is part of
+ the result. That is, only tasks that are expected to be
+ CPU bound are part of the result.</p>
+ </desc>
+ </func>
+
+ <func>
+ <name name="statistics" arity="1" clause_i="2"/>
+ <fsummary>Information about active processes and ports.</fsummary>
+ <desc>
+ <marker id="statistics_active_tasks_all"></marker>
<p>Returns a list where each element represents the amount
of active processes and ports on each run queue and its
- associated scheduler. That is, the number of processes and
- ports that are ready to run, or are currently running. The
- element location in the list corresponds to the scheduler
- and its run queue. The first element corresponds to scheduler
- number 1 and so on. The information is <em>not</em> gathered
- atomically. That is, the result is not necessarily a
- consistent snapshot of the state, but instead quite
- efficiently gathered.</p>
+ associated schedulers. That is, the number of processes and
+ ports that are ready to run, or are currently running.
+ Values for normal run queues and their associated schedulers
+ are located first in the resulting list. The first element
+ corresponds to scheduler number 1 and so on. If support for
+ dirty schedulers exist, an element with the value for the
+ dirty CPU run queue and its associated dirty CPU schedulers
+ follow and then as last element the value for the the dirty
+ IO run queue and its associated dirty IO schedulers follow.
+ The information is <em>not</em> gathered atomically. That is,
+ the result is not necessarily a consistent snapshot of the
+ state, but instead quite efficiently gathered.</p>
+ <note><p>Each normal scheduler has one run queue that it
+ manages. If dirty schedulers schedulers are supported, all
+ dirty CPU schedulers share one run queue, and all dirty IO
+ schedulers share one run queue. That is, we have multiple
+ normal run queues, one dirty CPU run queue and one dirty
+ IO run queue. Work can <em>not</em> migrate between the
+ different types of run queues. Only work in normal run
+ queues can migrate to other normal run queues. This has
+ to be taken into account when evaluating the result.</p></note>
<p>See also
<seealso marker="#statistics_total_active_tasks">
<c>statistics(total_active_tasks)</c></seealso>,
<seealso marker="#statistics_run_queue_lengths">
- <c>statistics(run_queue_lengths)</c></seealso>, and
+ <c>statistics(run_queue_lengths)</c></seealso>,
+ <seealso marker="#statistics_run_queue_lengths_all">
+ <c>statistics(run_queue_lengths_all)</c></seealso>,
<seealso marker="#statistics_total_run_queue_lengths">
- <c>statistics(total_run_queue_lengths)</c></seealso>.</p>
+ <c>statistics(total_run_queue_lengths)</c></seealso>, and
+ <seealso marker="#statistics_total_run_queue_lengths_all">
+ <c>statistics(total_run_queue_lengths_all)</c></seealso>.</p>
</desc>
</func>
<func>
- <name name="statistics" arity="1" clause_i="2"/>
+ <name name="statistics" arity="1" clause_i="3"/>
<fsummary>Information about context switches.</fsummary>
<desc>
<p>Returns the total number of context switches since the
@@ -6154,7 +6186,7 @@ true</pre>
</func>
<func>
- <name name="statistics" arity="1" clause_i="3"/>
+ <name name="statistics" arity="1" clause_i="4"/>
<fsummary>Information about exact reductions.</fsummary>
<desc>
<marker id="statistics_exact_reductions"></marker>
@@ -6170,7 +6202,7 @@ true</pre>
</func>
<func>
- <name name="statistics" arity="1" clause_i="4"/>
+ <name name="statistics" arity="1" clause_i="5"/>
<fsummary>Information about garbage collection.</fsummary>
<desc>
<p>Returns information about garbage collection, for example:</p>
@@ -6182,7 +6214,7 @@ true</pre>
</func>
<func>
- <name name="statistics" arity="1" clause_i="5"/>
+ <name name="statistics" arity="1" clause_i="6"/>
<fsummary>Information about I/O.</fsummary>
<desc>
<p>Returns <c><anno>Input</anno></c>,
@@ -6193,7 +6225,7 @@ true</pre>
</func>
<func>
- <name name="statistics" arity="1" clause_i="6"/>
+ <name name="statistics" arity="1" clause_i="7"/>
<fsummary>Information about microstate accounting.</fsummary>
<desc>
<marker id="statistics_microstate_accounting"></marker>
@@ -6329,7 +6361,7 @@ lists:map(
</func>
<func>
- <name name="statistics" arity="1" clause_i="7"/>
+ <name name="statistics" arity="1" clause_i="8"/>
<fsummary>Information about reductions.</fsummary>
<desc>
<marker id="statistics_reductions"></marker>
@@ -6348,12 +6380,13 @@ lists:map(
</func>
<func>
- <name name="statistics" arity="1" clause_i="8"/>
+ <name name="statistics" arity="1" clause_i="9"/>
<fsummary>Information about the run-queues.</fsummary>
<desc><marker id="statistics_run_queue"></marker>
- <p>Returns the total length of the run-queues. That is, the number
+ <p>Returns the total length of all normal run-queues. That is, the number
of processes and ports that are ready to run on all available
- run-queues. The information is gathered atomically. That
+ normal run-queues. Dirty run queues are not part of the
+ result. The information is gathered atomically. That
is, the result is a consistent snapshot of the state, but
this operation is much more expensive compared to
<seealso marker="#statistics_total_run_queue_lengths">
@@ -6363,29 +6396,63 @@ lists:map(
</func>
<func>
- <name name="statistics" arity="1" clause_i="9"/>
+ <name name="statistics" arity="1" clause_i="10"/>
<fsummary>Information about the run-queue lengths.</fsummary>
<desc><marker id="statistics_run_queue_lengths"></marker>
+ <p>Returns the same as
+ <seealso marker="#statistics_run_queue_lengths_all">
+ <c>statistics(run_queue_lengths_all)</c></seealso>
+ with the exception that no information about the dirty
+ IO run queue is part of the result. That is, only
+ run queues with work that is expected to be CPU bound
+ is part of the result.</p>
+ </desc>
+ </func>
+
+ <func>
+ <name name="statistics" arity="1" clause_i="11"/>
+ <fsummary>Information about the run-queue lengths.</fsummary>
+ <desc><marker id="statistics_run_queue_lengths_all"></marker>
<p>Returns a list where each element represents the amount
- of processes and ports ready to run for each run queue. The
- element location in the list corresponds to the run queue
- of a scheduler. The first element corresponds to the run
- queue of scheduler number 1 and so on. The information is
- <em>not</em> gathered atomically. That is, the result is
- not necessarily a consistent snapshot of the state, but
- instead quite efficiently gathered.</p>
+ of processes and ports ready to run for each run queue.
+ Values for normal run queues are located first in the
+ resulting list. The first element corresponds to the
+ normal run queue of scheduler number 1 and so on. If
+ support for dirty schedulers exist, values for the dirty
+ CPU run queue and the dirty IO run queue follow (in that
+ order) at the end. The information is <em>not</em>
+ gathered atomically. That is, the result is not
+ necessarily a consistent snapshot of the state, but
+ instead quite efficiently gathered.</p>
+ <note><p>Each normal scheduler has one run queue that it
+ manages. If dirty schedulers schedulers are supported, all
+ dirty CPU schedulers share one run queue, and all dirty IO
+ schedulers share one run queue. That is, we have multiple
+ normal run queues, one dirty CPU run queue and one dirty
+ IO run queue. Work can <em>not</em> migrate between the
+ different types of run queues. Only work in normal run
+ queues can migrate to other normal run queues. This has
+ to be taken into account when evaluating the result.</p></note>
<p>See also
+ <seealso marker="#statistics_run_queue_lengths">
+ <c>statistics(run_queue_lengths)</c></seealso>,
+ <seealso marker="#statistics_total_run_queue_lengths_all">
+ <c>statistics(total_run_queue_lengths_all)</c></seealso>,
<seealso marker="#statistics_total_run_queue_lengths">
<c>statistics(total_run_queue_lengths)</c></seealso>,
<seealso marker="#statistics_active_tasks">
- <c>statistics(active_tasks)</c></seealso>, and
+ <c>statistics(active_tasks)</c></seealso>,
+ <seealso marker="#statistics_active_tasks_all">
+ <c>statistics(active_tasks_all)</c></seealso>, and
<seealso marker="#statistics_total_active_tasks">
- <c>statistics(total_active_tasks)</c></seealso>.</p>
+ <c>statistics(total_active_tasks)</c></seealso>,
+ <seealso marker="#statistics_total_active_tasks_all">
+ <c>statistics(total_active_tasks_all)</c></seealso>.</p>
</desc>
</func>
<func>
- <name name="statistics" arity="1" clause_i="10"/>
+ <name name="statistics" arity="1" clause_i="12"/>
<fsummary>Information about runtime.</fsummary>
<desc>
<p>Returns information about runtime, in milliseconds.</p>
@@ -6400,7 +6467,7 @@ lists:map(
</func>
<func>
- <name name="statistics" arity="1" clause_i="11"/>
+ <name name="statistics" arity="1" clause_i="13"/>
<fsummary>Information about each schedulers work time.</fsummary>
<desc>
<marker id="statistics_scheduler_wall_time"></marker>
@@ -6521,7 +6588,7 @@ ok
</func>
<func>
- <name name="statistics" arity="1" clause_i="12"/>
+ <name name="statistics" arity="1" clause_i="14"/>
<fsummary>Information about each schedulers work time.</fsummary>
<desc>
<marker id="statistics_scheduler_wall_time_all"></marker>
@@ -6546,47 +6613,47 @@ ok
</desc>
</func>
<func>
- <name name="statistics" arity="1" clause_i="13"/>
+ <name name="statistics" arity="1" clause_i="15"/>
<fsummary>Information about active processes and ports.</fsummary>
<desc><marker id="statistics_total_active_tasks"></marker>
- <p>Returns the total amount of active processes and ports in
- the system. That is, the number of processes and ports that
- are ready to run, or are currently running. The information
- is <em>not</em> gathered atomically. That is, the result
- is not necessarily a consistent snapshot of the state, but
- instead quite efficiently gathered.</p>
- <p>See also
- <seealso marker="#statistics_active_tasks">
- <c>statistics(active_tasks)</c></seealso>,
- <seealso marker="#statistics_run_queue_lengths">
- <c>statistics(run_queue_lengths)</c></seealso>, and
- <seealso marker="#statistics_total_run_queue_lengths">
- <c>statistics(total_run_queue_lengths)</c></seealso>.</p>
+ <p>The same as calling
+ <c>lists:sum(</c><seealso marker="#statistics_active_tasks"><c>statistics(active_tasks)</c></seealso><c>)</c>,
+ but more efficient.</p>
</desc>
</func>
<func>
- <name name="statistics" arity="1" clause_i="14"/>
+ <name name="statistics" arity="1" clause_i="16"/>
+ <fsummary>Information about active processes and ports.</fsummary>
+ <desc><marker id="statistics_total_active_tasks_all"></marker>
+ <p>The same as calling
+ <c>lists:sum(</c><seealso marker="#statistics_active_tasks_all"><c>statistics(active_tasks_all)</c></seealso><c>)</c>,
+ but more efficient.</p>
+ </desc>
+ </func>
+
+ <func>
+ <name name="statistics" arity="1" clause_i="17"/>
<fsummary>Information about the run-queue lengths.</fsummary>
<desc><marker id="statistics_total_run_queue_lengths"></marker>
- <p>Returns the total length of the run queues. That is, the number
- of processes and ports that are ready to run on all available
- run queues. The information is <em>not</em> gathered atomically.
- That is, the result is not necessarily a consistent snapshot of
- the state, but much more efficiently gathered compared to
- <seealso marker="#statistics_run_queue">
- <c>statistics(run_queue)</c></seealso>.</p>
- <p>See also <seealso marker="#statistics_run_queue_lengths">
- <c>statistics(run_queue_lengths)</c></seealso>,
- <seealso marker="#statistics_total_active_tasks">
- <c>statistics(total_active_tasks)</c></seealso>, and
- <seealso marker="#statistics_active_tasks">
- <c>statistics(active_tasks)</c></seealso>.</p>
+ <p>The same as calling
+ <c>lists:sum(</c><seealso marker="#statistics_run_queue_lengths"><c>statistics(run_queue_lengths)</c></seealso><c>)</c>,
+ but more efficient.</p>
</desc>
</func>
<func>
- <name name="statistics" arity="1" clause_i="15"/>
+ <name name="statistics" arity="1" clause_i="18"/>
+ <fsummary>Information about the run-queue lengths.</fsummary>
+ <desc><marker id="statistics_total_run_queue_lengths_all"></marker>
+ <p>The same as calling
+ <c>lists:sum(</c><seealso marker="#statistics_run_queue_lengths_all"><c>statistics(run_queue_lengths_all)</c></seealso><c>)</c>,
+ but more efficient.</p>
+ </desc>
+ </func>
+
+ <func>
+ <name name="statistics" arity="1" clause_i="19"/>
<fsummary>Information about wall clock.</fsummary>
<desc>
<p>Returns information about wall clock. <c>wall_clock</c> can