change system file

hc

2024-10-09 244b2c5ca8b14627e4a17755e5922221e121c771

 kernel/tools/perf/Documentation/perf-diff.txt
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@@ -90,9 +90,15 @@
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 -c::
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 --compute::
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-        Differential computation selection - delta, ratio, wdiff, delta-abs
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-        (default is delta-abs).  Default can be changed using diff.compute
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-        config option.  See COMPARISON METHODS section for more info.
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+        Differential computation selection - delta, ratio, wdiff, cycles,
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+        delta-abs (default is delta-abs).  Default can be changed using
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+        diff.compute config option.  See COMPARISON METHODS section for
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+        more info.
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+
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+--cycles-hist::
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+	Report a histogram and the standard deviation for cycles data.
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+	It can help us to judge if the reported cycles data is noisy or
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+	not. This option should be used with '-c cycles'.
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 -p::
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 --period::
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 	"relative" means it's relative to filtered entries only so that the
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 	sum of shown entries will be always 100%.  "absolute" means it retains
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 	the original value before and after the filter is applied.
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+
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+--time::
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+	Analyze samples within given time window. It supports time
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+	percent with multiple time ranges. Time string is 'a%/n,b%/m,...'
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+	or 'a%-b%,c%-%d,...'.
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+
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+	For example:
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+
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+	Select the second 10% time slice to diff:
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+
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+	  perf diff --time 10%/2
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+
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+	Select from 0% to 10% time slice to diff:
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+
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+	  perf diff --time 0%-10%
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+
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+	Select the first and the second 10% time slices to diff:
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+
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+	  perf diff --time 10%/1,10%/2
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+
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+	Select from 0% to 10% and 30% to 40% slices to diff:
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+
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+	  perf diff --time 0%-10%,30%-40%
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+
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+	It also supports analyzing samples within a given time window
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+	<start>,<stop>. Times have the format seconds.nanoseconds. If 'start'
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+	is not given (i.e. time string is ',x.y') then analysis starts at
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+	the beginning of the file. If stop time is not given (i.e. time
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+	string is 'x.y,') then analysis goes to the end of the file.
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+	Multiple ranges can be separated by spaces, which requires the argument
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+	to be quoted e.g. --time "1234.567,1234.789 1235,"
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+	Time string is'a1.b1,c1.d1:a2.b2,c2.d2'. Use ':' to separate timestamps
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+	for different perf.data files.
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+
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+	For example, we get the timestamp information from 'perf script'.
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+
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+	  perf script -i perf.data.old
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+	    mgen 13940 [000]  3946.361400: ...
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+
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+	  perf script -i perf.data
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+	    mgen 13940 [000]  3971.150589 ...
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+
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+	  perf diff --time 3946.361400,:3971.150589,
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+
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+	It analyzes the perf.data.old from the timestamp 3946.361400 to
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+	the end of perf.data.old and analyzes the perf.data from the
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+	timestamp 3971.150589 to the end of perf.data.
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+
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+--cpu:: Only diff samples for the list of CPUs provided. Multiple CPUs can
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+	be provided as a comma-separated list with no space: 0,1. Ranges of
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+	CPUs are specified with -: 0-2. Default is to report samples on all
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+	CPUs.
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+
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+--pid=::
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+	Only diff samples for given process ID (comma separated list).
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+
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+--tid=::
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+	Only diff samples for given thread ID (comma separated list).
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+
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+--stream::
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+	Enable hot streams comparison. Stream can be a callchain which is
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+	aggregated by the branch records from samples.
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 COMPARISON
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 ----------
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     - WEIGHT-A being the weight of the data file
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     - WEIGHT-B being the weight of the baseline data file
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+cycles
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+~~~~~~
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+If specified the '[Program Block Range] Cycles Diff' column is displayed.
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+It displays the cycles difference of same program basic block amongst
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+two perf.data. The program basic block is the code between two branches.
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+
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+'[Program Block Range]' indicates the range of a program basic block.
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+Source line is reported if it can be found otherwise uses symbol+offset
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+instead.
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+
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 SEE ALSO
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 --------
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 linkperf:perf-record[1], linkperf:perf-report[1]