aboutsummaryrefslogtreecommitdiffstats
path: root/erts/doc/src
diff options
context:
space:
mode:
Diffstat (limited to 'erts/doc/src')
-rw-r--r--erts/doc/src/erl_driver.xml112
-rw-r--r--erts/doc/src/erl_nif.xml112
-rw-r--r--erts/doc/src/erlang.xml64
3 files changed, 284 insertions, 4 deletions
diff --git a/erts/doc/src/erl_driver.xml b/erts/doc/src/erl_driver.xml
index e717fc0c4e..e338e95938 100644
--- a/erts/doc/src/erl_driver.xml
+++ b/erts/doc/src/erl_driver.xml
@@ -347,6 +347,16 @@
the driver does not handle sizes that overflow an <c>int</c>
all will work as before.</p>
</item>
+ <tag><marker id="time_measurement"/>Time Measurement</tag>
+ <item><p>Support for time measurement in drivers:
+ <list>
+ <item><seealso marker="#ErlDrvTime"><c>ErlDrvTime</c></seealso></item>
+ <item><seealso marker="#ErlDrvTimeUnit"><c>ErlDrvTimeUnit</c></seealso></item>
+ <item><seealso marker="#erl_drv_monotonic_time"><c>erl_drv_monotonic_time()</c></seealso></item>
+ <item><seealso marker="#erl_drv_time_offset"><c>erl_drv_time_offset()</c></seealso></item>
+ <item><seealso marker="#erl_drv_convert_time_unit"><c>erl_drv_convert_time_unit()</c></seealso></item>
+ </list></p>
+ </item>
</taglist>
</section>
@@ -860,6 +870,24 @@ typedef struct ErlIOVec {
<seealso marker="#erl_drv_tsd_get">erl_drv_tsd_get()</seealso>.
</p>
</item>
+ <tag><marker id="ErlDrvTime"/>ErlDrvTime</tag>
+ <item>
+ <p>A signed 64-bit integer type for representation of time.</p>
+ </item>
+ <tag><marker id="ErlDrvTimeUnit"/>ErlDrvTimeUnit</tag>
+ <item>
+ <p>An enumeration of time units supported by the driver API:</p>
+ <taglist>
+ <tag><c>ERL_DRV_SEC</c></tag>
+ <item><p>Seconds</p></item>
+ <tag><c>ERL_DRV_MSEC</c></tag>
+ <item><p>Milliseconds</p></item>
+ <tag><c>ERL_DRV_USEC</c></tag>
+ <item><p>Microseconds</p></item>
+ <tag><c>ERL_DRV_NSEC</c></tag>
+ <item><p>Nanoseconds</p></item>
+ </taglist>
+ </item>
</taglist>
</section>
@@ -1023,6 +1051,10 @@ typedef struct ErlIOVec {
<fsummary>Read a system timestamp</fsummary>
<desc>
<marker id="driver_get_now"></marker>
+ <warning><p><em>This function is deprecated! Do not use it!</em>
+ Use the documented
+ <seealso marker="#time_measurement">time measurement functionality</seealso>
+ instead.</p></warning>
<p>This function reads a timestamp into the memory pointed to by
the parameter <c>now</c>. See the description of <seealso marker="#ErlDrvNowData">ErlDrvNowData</seealso> for
specification of its fields. </p>
@@ -2997,6 +3029,86 @@ ERL_DRV_MAP int sz
</desc>
</func>
+ <func>
+ <name><ret>ErlDrvTime</ret><nametext>erl_drv_monotonic_time(ErlDrvTimeUnit time_unit)</nametext></name>
+ <fsummary>Get Erlang Monotonic Time</fsummary>
+ <desc>
+ <marker id="erl_drv_monotonic_time"></marker>
+ <p>Arguments:</p>
+ <taglist>
+ <tag><c>time_unit</c></tag>
+ <item>Time unit of returned value.</item>
+ </taglist>
+ <p>
+ Returns
+ <seealso marker="time_correction#Erlang_Monotonic_Time">Erlang
+ monotonic time</seealso>. Note that it is not uncommon with
+ negative values.
+ </p>
+ <p>Returns <c>ERL_DRV_TIME_ERROR</c> if called with an invalid
+ time unit argument, or if called from a thread that is not a
+ scheduler thread.</p>
+ <p>See also:</p>
+ <list>
+ <item><seealso marker="#ErlDrvTime"><c>ErlDrvTime</c></seealso></item>
+ <item><seealso marker="#ErlDrvTimeUnit"><c>ErlDrvTimeUnit</c></seealso></item>
+ </list>
+ </desc>
+ </func>
+
+ <func>
+ <name><ret>ErlDrvTime</ret><nametext>erl_drv_time_offset(ErlDrvTimeUnit time_unit)</nametext></name>
+ <fsummary>Get current Time Offset</fsummary>
+ <desc>
+ <marker id="erl_drv_time_offset"></marker>
+ <p>Arguments:</p>
+ <taglist>
+ <tag><c>time_unit</c></tag>
+ <item>Time unit of returned value.</item>
+ </taglist>
+ <p>Returns the current time offset between
+ <seealso marker="time_correction#Erlang_Monotonic_Time">Erlang monotonic time</seealso>
+ and
+ <seealso marker="time_correction#Erlang_System_Time">Erlang system time</seealso>
+ converted into the <c>time_unit</c> passed as argument.</p>
+ <p>Returns <c>ERL_DRV_TIME_ERROR</c> if called with an invalid
+ time unit argument, or if called from a thread that is not a
+ scheduler thread.</p>
+ <p>See also:</p>
+ <list>
+ <item><seealso marker="#ErlDrvTime"><c>ErlDrvTime</c></seealso></item>
+ <item><seealso marker="#ErlDrvTimeUnit"><c>ErlDrvTimeUnit</c></seealso></item>
+ </list>
+ </desc>
+ </func>
+
+ <func>
+ <name><ret>ErlDrvTime</ret><nametext>erl_drv_convert_time_unit(ErlDrvTime val, ErlDrvTimeUnit from, ErlDrvTimeUnit to)</nametext></name>
+ <fsummary>Convert time unit of a time value</fsummary>
+ <desc>
+ <marker id="erl_drv_convert_time_unit"></marker>
+ <p>Arguments:</p>
+ <taglist>
+ <tag><c>val</c></tag>
+ <item>Value to convert time unit for.</item>
+ <tag><c>from</c></tag>
+ <item>Time unit of <c>val</c>.</item>
+ <tag><c>to</c></tag>
+ <item>Time unit of returned value.</item>
+ </taglist>
+ <p>Converts the <c>val</c> value of time unit <c>from</c> to
+ the corresponding value of time unit <c>to</c>. The result is
+ rounded using the floor function.</p>
+ <p>Returns <c>ERL_DRV_TIME_ERROR</c> if called with an invalid
+ time unit argument.</p>
+ <p>See also:</p>
+ <list>
+ <item><seealso marker="#ErlDrvTime"><c>ErlDrvTime</c></seealso></item>
+ <item><seealso marker="#ErlDrvTimeUnit"><c>ErlDrvTimeUnit</c></seealso></item>
+ </list>
+ </desc>
+ </func>
+
</funcs>
<section>
<title>SEE ALSO</title>
diff --git a/erts/doc/src/erl_nif.xml b/erts/doc/src/erl_nif.xml
index 2d8706169f..420c9fea38 100644
--- a/erts/doc/src/erl_nif.xml
+++ b/erts/doc/src/erl_nif.xml
@@ -317,6 +317,17 @@ ok
libraries might however fail if deprecated features are used.
</p></item>
+ <tag><marker id="time_measurement"/>Time Measurement</tag>
+ <item><p>Support for time measurement in NIF libraries:
+ <list>
+ <item><seealso marker="#ErlNifTime"><c>ErlNifTime</c></seealso></item>
+ <item><seealso marker="#ErlNifTimeUnit"><c>ErlNifTimeUnit</c></seealso></item>
+ <item><seealso marker="#enif_monotonic_time"><c>enif_monotonic_time()</c></seealso></item>
+ <item><seealso marker="#enif_time_offset"><c>enif_time_offset()</c></seealso></item>
+ <item><seealso marker="#enif_convert_time_unit"><c>enif_convert_time_unit()</c></seealso></item>
+ </list></p>
+ </item>
+
<tag>Long-running NIFs</tag>
<item><p><marker id="dirty_nifs"/>Native functions
<seealso marker="#lengthy_work">
@@ -560,6 +571,25 @@ typedef enum {
<item><p>A native signed 64-bit integer type.</p></item>
<tag><marker id="ErlNifUInt64"/>ErlNifUInt64</tag>
<item><p>A native unsigned 64-bit integer type.</p></item>
+
+ <tag><marker id="ErlNifTime"/>ErlNifTime</tag>
+ <item>
+ <p>A signed 64-bit integer type for representation of time.</p>
+ </item>
+ <tag><marker id="ErlNifTimeUnit"/>ErlNifTimeUnit</tag>
+ <item>
+ <p>An enumeration of time units supported by the NIF API:</p>
+ <taglist>
+ <tag><c>ERL_NIF_SEC</c></tag>
+ <item><p>Seconds</p></item>
+ <tag><c>ERL_NIF_MSEC</c></tag>
+ <item><p>Milliseconds</p></item>
+ <tag><c>ERL_NIF_USEC</c></tag>
+ <item><p>Microseconds</p></item>
+ <tag><c>ERL_NIF_NSEC</c></tag>
+ <item><p>Nanoseconds</p></item>
+ </taglist>
+ </item>
</taglist>
</section>
@@ -1486,6 +1516,88 @@ enif_map_iterator_destroy(env, &amp;iter);
<desc><p>Same as <seealso marker="erl_driver#erl_drv_tsd_set">erl_drv_tsd_set</seealso>.
</p></desc>
</func>
+
+
+ <func>
+ <name><ret>ErlNifTime</ret><nametext>enif_monotonic_time(ErlNifTimeUnit time_unit)</nametext></name>
+ <fsummary>Get Erlang Monotonic Time</fsummary>
+ <desc>
+ <marker id="enif_monotonic_time"></marker>
+ <p>Arguments:</p>
+ <taglist>
+ <tag><c>time_unit</c></tag>
+ <item>Time unit of returned value.</item>
+ </taglist>
+ <p>
+ Returns
+ <seealso marker="time_correction#Erlang_Monotonic_Time">Erlang
+ monotonic time</seealso>. Note that it is not uncommon with
+ negative values.
+ </p>
+ <p>Returns <c>ERL_NIF_TIME_ERROR</c> if called with an invalid
+ time unit argument, or if called from a thread that is not a
+ scheduler thread.</p>
+ <p>See also:</p>
+ <list>
+ <item><seealso marker="#ErlNifTime"><c>ErlNifTime</c></seealso></item>
+ <item><seealso marker="#ErlNifTimeUnit"><c>ErlNifTimeUnit</c></seealso></item>
+ </list>
+ </desc>
+ </func>
+
+ <func>
+ <name><ret>ErlNifTime</ret><nametext>enif_time_offset(ErlNifTimeUnit time_unit)</nametext></name>
+ <fsummary>Get current Time Offset</fsummary>
+ <desc>
+ <marker id="enif_time_offset"></marker>
+ <p>Arguments:</p>
+ <taglist>
+ <tag><c>time_unit</c></tag>
+ <item>Time unit of returned value.</item>
+ </taglist>
+ <p>Returns the current time offset between
+ <seealso marker="time_correction#Erlang_Monotonic_Time">Erlang monotonic time</seealso>
+ and
+ <seealso marker="time_correction#Erlang_System_Time">Erlang system time</seealso>
+ converted into the <c>time_unit</c> passed as argument.</p>
+ <p>Returns <c>ERL_NIF_TIME_ERROR</c> if called with an invalid
+ time unit argument, or if called from a thread that is not a
+ scheduler thread.</p>
+ <p>See also:</p>
+ <list>
+ <item><seealso marker="#ErlNifTime"><c>ErlNifTime</c></seealso></item>
+ <item><seealso marker="#ErlNifTimeUnit"><c>ErlNifTimeUnit</c></seealso></item>
+ </list>
+ </desc>
+ </func>
+
+ <func>
+ <name><ret>ErlNifTime</ret><nametext>enif_convert_time_unit(ErlNifTime val, ErlNifTimeUnit from, ErlNifTimeUnit to)</nametext></name>
+ <fsummary>Convert time unit of a time value</fsummary>
+ <desc>
+ <marker id="enif_convert_time_unit"></marker>
+ <p>Arguments:</p>
+ <taglist>
+ <tag><c>val</c></tag>
+ <item>Value to convert time unit for.</item>
+ <tag><c>from</c></tag>
+ <item>Time unit of <c>val</c>.</item>
+ <tag><c>to</c></tag>
+ <item>Time unit of returned value.</item>
+ </taglist>
+ <p>Converts the <c>val</c> value of time unit <c>from</c> to
+ the corresponding value of time unit <c>to</c>. The result is
+ rounded using the floor function.</p>
+ <p>Returns <c>ERL_NIF_TIME_ERROR</c> if called with an invalid
+ time unit argument.</p>
+ <p>See also:</p>
+ <list>
+ <item><seealso marker="#ErlNifTime"><c>ErlNifTime</c></seealso></item>
+ <item><seealso marker="#ErlNifTimeUnit"><c>ErlNifTimeUnit</c></seealso></item>
+ </list>
+ </desc>
+ </func>
+
</funcs>
<section>
<title>SEE ALSO</title>
diff --git a/erts/doc/src/erlang.xml b/erts/doc/src/erlang.xml
index 13b16d1ed3..964601f195 100644
--- a/erts/doc/src/erlang.xml
+++ b/erts/doc/src/erlang.xml
@@ -7739,6 +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
@@ -7759,6 +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>
@@ -8118,7 +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
@@ -8126,6 +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.
@@ -8172,9 +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>
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-22 18:36:47 +0000