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-rw-r--r--erts/doc/src/erlang.xml33
-rw-r--r--erts/doc/src/time_correction.xml29
2 files changed, 49 insertions, 13 deletions
diff --git a/erts/doc/src/erlang.xml b/erts/doc/src/erlang.xml
index 98c0ef5f81..7cb417ac92 100644
--- a/erts/doc/src/erlang.xml
+++ b/erts/doc/src/erlang.xml
@@ -110,10 +110,17 @@
<note>
<p>The value of the <c>native</c> time unit gives
you more or less no information at all about the
- quality of time values. It sets an upper bound for
- the resolution as well as for the precision, but it
- gives absolutely no information at all about the
- accuracy.</p>
+ quality of time values. It sets a limit for
+ the
+ <seealso marker="time_correction#Time_Resolution">resolution</seealso>
+ as well as for the
+ <seealso marker="time_correction#Time_Precision">precision</seealso>
+ of time values,
+ but it gives absolutely no information at all about the
+ <seealso marker="time_correction#Time_Accuracy">accuracy</seealso>
+ of time values. The resolution of the <c>native</c> time
+ unit and the resolution of time values may differ
+ significantly.</p>
</note>
</item>
@@ -6435,18 +6442,22 @@ ok
<c>Function</c>.</p></item>
<tag><c>{resolution, OsMonotonicTimeResolution}</c></tag>
- <item><p>Highest possible resolution of current
- OS monotonic time source as parts per second. If
- no resolution information can be retreived from
- the OS, <c>OsMonotonicTimeResolution</c> will be
+ <item><p>Highest possible
+ <seealso marker="time_correction#Time_Resolution">resolution</seealso>
+ of current OS monotonic time source as parts per
+ second. If no resolution information can be retreived
+ from the OS, <c>OsMonotonicTimeResolution</c> will be
set to the resolution of the time unit of
<c>Function</c>s return value. That is, the actual
resolution may be lower than
<c>OsMonotonicTimeResolution</c>. Also note that
the resolution does not say anything about the
- accuracy, and that the precision might not align
- with the resolution. You do, however, know that the
- precision won't be higher than
+ <seealso marker="time_correction#Time_Accuracy">accuracy</seealso>,
+ and that the
+ <seealso marker="time_correction#Time_Precision">precision</seealso>
+ might not align with the resolution. You do,
+ however, know that the precision won't be
+ better than
<c>OsMonotonicTimeResolution</c>.</p></item>
<tag><c>{extended, Extended}</c></tag>
diff --git a/erts/doc/src/time_correction.xml b/erts/doc/src/time_correction.xml
index 3bc3d04186..ed658ff58c 100644
--- a/erts/doc/src/time_correction.xml
+++ b/erts/doc/src/time_correction.xml
@@ -114,6 +114,29 @@
happened yet), POSIX time would make a one second leap forward.</p>
</section>
+ <marker id="Time_Resolution"/>
+ <section>
+ <title>Time Resolution</title>
+ <p>The shortest time interval that can be distinguished when
+ reading time values.</p>
+ </section>
+
+ <marker id="Time_Precision"/>
+ <section>
+ <title>Time Precision</title>
+ <p>The shortest time interval that can be be distinguished
+ repeatedly and reliably when reading time values. Precision
+ is limited by the
+ <seealso marker="#Time_Resolution">resolution</seealso>, but
+ resolution and precision might differ significantly.</p>
+ </section>
+
+ <marker id="Time_Accuracy"/>
+ <section>
+ <title>Time Accuracy</title>
+ <p>The correctness of time values.</p>
+ </section>
+
<marker id="OS_System_Time"/>
<section>
<title>OS System Time</title>
@@ -162,8 +185,10 @@
Erlang runtime system. The Erlang monotonic time increase since
some unspecified point in time. It can be retrieved by calling
<seealso marker="erlang#monotonic_time/0"><c>erlang:monotonic_time()</c></seealso>.
- The accuracy, and precision of Erlang monotonic time heavily
- depends on the accuracy and precision of
+ The
+ <seealso marker="#Time_Accuracy">accuracy</seealso>, and
+ <seealso marker="#Time_Precision">precision</seealso> of Erlang
+ monotonic time heavily depends on the accuracy and precision of
<seealso marker="#OS_Monotonic_Time">OS monotonic time</seealso>,
the accuracy and precision of
<seealso marker="#OS_System_Time">OS system time</seealso> as well