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Stephane Eranian
4aa9015f8b
This patch adds an option (-o) to save the output of perf stat into a
file. You could do this with perf record but not with perf stat.
Instead, you had to fiddle with stderr to save the counts into a
separate file.
The patch also adds the --append option so that results can be
concatenated into a single file across runs. Each run of the tool is
clearly separated by a comment line starting with a hash mark. The -A
option of perf record is already used by perf stat, so we only add a
long option.
$ perf stat -o res.txt date
$ cat res.txt
Performance counter stats for 'date':
0.791306 task-clock # 0.668 CPUs utilized
2 context-switches # 0.003 M/sec
0 CPU-migrations # 0.000 M/sec
197 page-faults # 0.249 M/sec
1878143 cycles # 2.373 GHz
<not supported> stalled-cycles-frontend
<not supported> stalled-cycles-backend
1083367 instructions # 0.58 insns per cycle
193027 branches # 243.935 M/sec
9014 branch-misses # 4.67% of all branches
0.001184746 seconds time elapsed
The option can be combined with -x to make the output file much easier
to parse.
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20110815202233.GA18535@quad
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
125 lines
3.3 KiB
Plaintext
125 lines
3.3 KiB
Plaintext
perf-stat(1)
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============
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NAME
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----
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perf-stat - Run a command and gather performance counter statistics
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SYNOPSIS
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--------
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[verse]
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'perf stat' [-e <EVENT> | --event=EVENT] [-a] <command>
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'perf stat' [-e <EVENT> | --event=EVENT] [-a] -- <command> [<options>]
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DESCRIPTION
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-----------
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This command runs a command and gathers performance counter statistics
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from it.
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OPTIONS
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-------
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<command>...::
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Any command you can specify in a shell.
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-e::
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--event=::
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Select the PMU event. Selection can be a symbolic event name
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(use 'perf list' to list all events) or a raw PMU
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event (eventsel+umask) in the form of rNNN where NNN is a
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hexadecimal event descriptor.
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-i::
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--no-inherit::
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child tasks do not inherit counters
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-p::
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--pid=<pid>::
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stat events on existing process id
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-t::
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--tid=<tid>::
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stat events on existing thread id
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-a::
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--all-cpus::
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system-wide collection from all CPUs
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-c::
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--scale::
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scale/normalize counter values
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-r::
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--repeat=<n>::
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repeat command and print average + stddev (max: 100)
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-B::
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--big-num::
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print large numbers with thousands' separators according to locale
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-C::
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--cpu=::
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Count only on the list of CPUs provided. Multiple CPUs can be provided as a
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comma-separated list with no space: 0,1. Ranges of CPUs are specified with -: 0-2.
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In per-thread mode, this option is ignored. The -a option is still necessary
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to activate system-wide monitoring. Default is to count on all CPUs.
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-A::
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--no-aggr::
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Do not aggregate counts across all monitored CPUs in system-wide mode (-a).
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This option is only valid in system-wide mode.
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-n::
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--null::
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null run - don't start any counters
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-v::
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--verbose::
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be more verbose (show counter open errors, etc)
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-x SEP::
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--field-separator SEP::
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print counts using a CSV-style output to make it easy to import directly into
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spreadsheets. Columns are separated by the string specified in SEP.
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-G name::
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--cgroup name::
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monitor only in the container (cgroup) called "name". This option is available only
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in per-cpu mode. The cgroup filesystem must be mounted. All threads belonging to
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container "name" are monitored when they run on the monitored CPUs. Multiple cgroups
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can be provided. Each cgroup is applied to the corresponding event, i.e., first cgroup
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to first event, second cgroup to second event and so on. It is possible to provide
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an empty cgroup (monitor all the time) using, e.g., -G foo,,bar. Cgroups must have
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corresponding events, i.e., they always refer to events defined earlier on the command
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line.
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-o file::
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-output file::
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Print the output into the designated file.
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--append::
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Append to the output file designated with the -o option. Ignored if -o is not specified.
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EXAMPLES
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--------
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$ perf stat -- make -j
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Performance counter stats for 'make -j':
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8117.370256 task clock ticks # 11.281 CPU utilization factor
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678 context switches # 0.000 M/sec
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133 CPU migrations # 0.000 M/sec
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235724 pagefaults # 0.029 M/sec
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24821162526 CPU cycles # 3057.784 M/sec
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18687303457 instructions # 2302.138 M/sec
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172158895 cache references # 21.209 M/sec
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27075259 cache misses # 3.335 M/sec
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Wall-clock time elapsed: 719.554352 msecs
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SEE ALSO
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--------
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linkperf:perf-top[1], linkperf:perf-list[1]
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