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-rw-r--r--erts/doc/src/erlang.xml179
1 files changed, 161 insertions, 18 deletions
diff --git a/erts/doc/src/erlang.xml b/erts/doc/src/erlang.xml
index c37ed3bea5..964601f195 100644
--- a/erts/doc/src/erlang.xml
+++ b/erts/doc/src/erlang.xml
@@ -5684,8 +5684,31 @@ true</pre>
<anno>Dest</anno>, <anno>Msg</anno>, [])</c></seealso>.</p>
</desc>
</func>
+
<func>
<name name="statistics" arity="1" clause_i="1"/>
+ <fsummary>Information about active processes and ports.</fsummary>
+ <desc><marker id="statistics_active_tasks"></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. 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
+ <seealso marker="#statistics_total_run_queue_lengths"><c>statistics(total_run_queue_lengths)</c></seealso>.
+ </p>
+ </desc>
+ </func>
+
+ <func>
+ <name name="statistics" arity="1" clause_i="2"/>
<fsummary>Information about context switches.</fsummary>
<desc>
<p>Returns the total number of context switches since the
@@ -5694,7 +5717,7 @@ true</pre>
</func>
<func>
- <name name="statistics" arity="1" clause_i="2"/>
+ <name name="statistics" arity="1" clause_i="3"/>
<fsummary>Information about exact reductions.</fsummary>
<desc>
<marker id="statistics_exact_reductions"></marker>
@@ -5708,7 +5731,7 @@ true</pre>
</func>
<func>
- <name name="statistics" arity="1" clause_i="3"/>
+ <name name="statistics" arity="1" clause_i="4"/>
<fsummary>Information about garbage collection.</fsummary>
<desc>
<p>Returns information about garbage collection, for example:</p>
@@ -5720,7 +5743,7 @@ true</pre>
</func>
<func>
- <name name="statistics" arity="1" clause_i="4"/>
+ <name name="statistics" arity="1" clause_i="5"/>
<fsummary>Information about I/O.</fsummary>
<desc>
<p>Returns <c><anno>Input</anno></c>,
@@ -5731,7 +5754,7 @@ true</pre>
</func>
<func>
- <name name="statistics" arity="1" clause_i="5"/>
+ <name name="statistics" arity="1" clause_i="6"/>
<fsummary>Information about reductions.</fsummary>
<desc>
<marker id="statistics_reductions"></marker>
@@ -5749,16 +5772,43 @@ true</pre>
</func>
<func>
- <name name="statistics" arity="1" clause_i="6"/>
- <fsummary>Information about the run-queue.</fsummary>
- <desc>
- <p>Returns the total length of run-queues, that is, the number
- of processes that are ready to run on all available run-queues.</p>
+ <name name="statistics" arity="1" clause_i="7"/>
+ <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
+ of processes and ports that are ready to run on all available
+ run-queues. 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"><c>statistics(total_run_queue_lengths)</c></seealso>.
+ This especially when a large amount of schedulers is used.
+ </p>
</desc>
</func>
<func>
- <name name="statistics" arity="1" clause_i="7"/>
+ <name name="statistics" arity="1" clause_i="8"/>
+ <fsummary>Information about the run-queue lengths.</fsummary>
+ <desc><marker id="statistics_run_queue_lengths"></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. See also,
+ <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
+ <seealso marker="#statistics_total_active_tasks"><c>statistics(total_active_tasks)</c></seealso>.
+ </p>
+ </desc>
+ </func>
+
+ <func>
+ <name name="statistics" arity="1" clause_i="9"/>
<fsummary>Information about runtime.</fsummary>
<desc>
<p>Returns information about runtime, in milliseconds.</p>
@@ -5773,7 +5823,7 @@ true</pre>
</func>
<func>
- <name name="statistics" arity="1" clause_i="8"/>
+ <name name="statistics" arity="1" clause_i="10"/>
<fsummary>Information about each schedulers work time.</fsummary>
<desc>
<marker id="statistics_scheduler_wall_time"></marker>
@@ -5844,7 +5894,44 @@ ok
</func>
<func>
- <name name="statistics" arity="1" clause_i="9"/>
+ <name name="statistics" arity="1" clause_i="11"/>
+ <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. 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>
+ </desc>
+ </func>
+
+ <func>
+ <name name="statistics" arity="1" clause_i="12"/>
+ <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>.
+ 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>
+ </desc>
+ </func>
+
+ <func>
+ <name name="statistics" arity="1" clause_i="13"/>
<fsummary>Information about wall clock.</fsummary>
<desc>
<p>Returns information about wall clock. <c>wall_clock</c> can
@@ -7652,6 +7739,13 @@ ok
<c>inactive</c>, and later <c>active</c> when the port
callback returns.</p>
</item>
+ <tag><c>monotonic_timestamp</c></tag>
+ <item>
+ <p>Timestamps in profile messages will use
+ <seealso marker="time_correction#Erlang_Monotonic_Time">Erlang
+ monotonic time</seealso>. The time-stamp (Ts) has the same
+ format and value as produced by <c>erlang:monotonic_time()</c>.</p>
+ </item>
<tag><c>runnable_procs</c></tag>
<item>
<p>If a process is put into or removed from the run queue, a
@@ -7672,6 +7766,25 @@ ok
<c>{profile, scheduler, Id, State, NoScheds, Ts}</c>, is
sent to <c><anno>ProfilerPid</anno></c>.</p>
</item>
+ <tag><c>strict_monotonic_timestamp</c></tag>
+ <item>
+ <p>Timestamps in profile messages will consisting of
+ <seealso marker="time_correction#Erlang_Monotonic_Time">Erlang
+ monotonic time</seealso> and a monotonically increasing
+ integer. The time-stamp (Ts) has the same format and value
+ as produced by <c>{erlang:monotonic_time(),
+ erlang:unique_integer([monotonic])}</c>.</p>
+ </item>
+ <tag><c>timestamp</c></tag>
+ <item>
+ <p>Timestamps in profile messages will include a
+ time-stamp (Ts) that has the same form as returned by
+ <c>erlang:now()</c>. This is also the default if no
+ timestamp flag is given. If <c>cpu_timestamp</c> has
+ been enabled via <c>erlang:trace/3</c>, this will also
+ effect the timestamp produced in profiling messages
+ when <c>timestamp</c> flag is enabled.</p>
+ </item>
</taglist>
<note><p><c>erlang:system_profile</c> is considered experimental
and its behavior can change in a future release.</p>
@@ -8031,7 +8144,10 @@ timestamp() ->
<tag><c>cpu_timestamp</c></tag>
<item>
<p>A global trace flag for the Erlang node that makes all
- trace time-stamps to be in CPU time, not wall clock time.
+ trace time-stamps using the <c>timestamp</c> flag to be
+ in CPU time, not wall clock time. That is, <c>cpu_timestamp</c>
+ will not be used if <c>monotonic_timestamp</c>, or
+ <c>strict_monotonic_timestamp</c> is enabled.
Only allowed with <c>PidSpec==all</c>. If the host
machine OS does not support high-resolution
CPU time measurements, <c>trace/3</c> exits with
@@ -8039,6 +8155,26 @@ timestamp() ->
not synchronize this value across cores, so be prepared
that time might seem to go backwards when using this option.</p>
</item>
+ <tag><c>monotonic_timestamp</c></tag>
+ <item>
+ <p>Includes an
+ <seealso marker="time_correction#Erlang_Monotonic_Time">Erlang
+ monotonic time</seealso> time-stamp in all trace messages. The
+ time-stamp (Ts) has the same format and value as produced by
+ <c>erlang:monotonic_time()</c>. This flag overrides
+ the <c>cpu_timestamp</c> flag.</p>
+ </item>
+ <tag><c>strict_monotonic_timestamp</c></tag>
+ <item>
+ <p>Includes an timestamp consisting of
+ <seealso marker="time_correction#Erlang_Monotonic_Time">Erlang
+ monotonic time</seealso> and a monotonically increasing
+ integer in all trace messages. The time-stamp (Ts) has the
+ same format and value as produced by
+ <c>{erlang:monotonic_time(),
+ erlang:unique_integer([monotonic])}</c>. This flag overrides
+ the <c>cpu_timestamp</c> flag.</p>
+ </item>
<tag><c>arity</c></tag>
<item>
<p>Used with the <c>call</c> trace flag.
@@ -8085,9 +8221,16 @@ timestamp() ->
in the following list. <c>Pid</c> is the process identifier of the
traced process in which the traced event has occurred. The
third tuple element is the message tag.</p>
- <p>If flag <c>timestamp</c> is given, the first tuple
- element is <c>trace_ts</c> instead, and the time-stamp
- is added last in the message tuple.</p>
+ <p>If flag <c>timestamp</c>, <c>strict_monotonic_timestamp</c>, or
+ <c>monotonic_timestamp</c> is given, the first tuple
+ element is <c>trace_ts</c> instead, and the time-stamp
+ is added as an extra element last in the message tuple. If
+ multiple timestamp flags are passed, <c>timestamp</c> has
+ precedence over <c>strict_monotonic_timestamp</c> which
+ in turn has precedence over <c>monotonic_timestamp</c>. All
+ timestamp flags are remembered, so if two are passed
+ and the one with highest precedence later is disabled
+ the other one will become active.</p>
<marker id="trace_3_trace_messages"></marker>
<taglist>
<tag><c>{trace, Pid, 'receive', Msg}</c></tag>
@@ -8182,14 +8325,14 @@ timestamp() ->
<p>When <c>Pid</c> is scheduled to run. The process
runs in function <c>{M, F, Arity}</c>. On some rare
occasions, the current function cannot be determined,
- then the last element <c>Arity</c> is <c>0</c>.</p>
+ then the last element is <c>0</c>.</p>
</item>
<tag><c>{trace, Pid, out, {M, F, Arity} | 0}</c></tag>
<item>
<p>When <c>Pid</c> is scheduled out. The process was
running in function {M, F, Arity}. On some rare occasions,
the current function cannot be determined, then the last
- element <c>Arity</c> is <c>0</c>.</p>
+ element is <c>0</c>.</p>
</item>
<tag><c>{trace, Pid, gc_start, Info}</c></tag>
<item>