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@@ -118,6 +118,62 @@ OPTIONS
sum of shown entries will be always 100%. "absolute" means it retains
the original value before and after the filter is applied.
+--time::
+ Analyze samples within given time window. It supports time
+ percent with multiple time ranges. Time string is 'a%/n,b%/m,...'
+ or 'a%-b%,c%-%d,...'.
+
+ For example:
+
+ Select the second 10% time slice to diff:
+
+ perf diff --time 10%/2
+
+ Select from 0% to 10% time slice to diff:
+
+ perf diff --time 0%-10%
+
+ Select the first and the second 10% time slices to diff:
+
+ perf diff --time 10%/1,10%/2
+
+ Select from 0% to 10% and 30% to 40% slices to diff:
+
+ perf diff --time 0%-10%,30%-40%
+
+ It also supports analyzing samples within a given time window
+ <start>,<stop>. Times have the format seconds.microseconds. If 'start'
+ is not given (i.e., time string is ',x.y') then analysis starts at
+ the beginning of the file. If stop time is not given (i.e, time
+ string is 'x.y,') then analysis goes to the end of the file. Time string is
+ 'a1.b1,c1.d1:a2.b2,c2.d2'. Use ':' to separate timestamps for different
+ perf.data files.
+
+ For example, we get the timestamp information from 'perf script'.
+
+ perf script -i perf.data.old
+ mgen 13940 [000] 3946.361400: ...
+
+ perf script -i perf.data
+ mgen 13940 [000] 3971.150589 ...
+
+ perf diff --time 3946.361400,:3971.150589,
+
+ It analyzes the perf.data.old from the timestamp 3946.361400 to
+ the end of perf.data.old and analyzes the perf.data from the
+ timestamp 3971.150589 to the end of perf.data.
+
+--cpu:: Only diff samples for the list of CPUs provided. Multiple CPUs can
+ be provided as a comma-separated list with no space: 0,1. Ranges of
+ CPUs are specified with -: 0-2. Default is to report samples on all
+ CPUs.
+
+--pid=::
+ Only diff samples for given process ID (comma separated list).
+
+--tid=::
+ Only diff samples for given thread ID (comma separated list).
+
COMPARISON
----------
The comparison is governed by the baseline file. The baseline perf.data