Perf - Revision history

Pchero at 12:05, 27 July 2016

2016-07-27T12:05:27Z

← Older revision		Revision as of 12:05, 27 July 2016
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	* https://perf.wiki.kernel.org/index.php/Main_Page - perf: Linux profiling with performance counters		* https://perf.wiki.kernel.org/index.php/Main_Page - perf: Linux profiling with performance counters

	[[category:~~linux~~]]		[[category:command/utility]]

Pchero: /* Example */

2016-05-04T09:16:16Z

Example

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 === Example ===
 <source lang=bash>
 $ perf stat --repeat 10 -e cycles:u -e instructions:u -e cache-references:u\
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 .609760790 seconds time elapsed                                          ( +-  0.70% )
 </source>

Pchero: /* Example */

2016-05-04T09:06:02Z

Example

@@ Line 49: / Line 49: @@
       -e cache-misses:u -e stalled-cycles-frontend:u -e stalled-cycles-backend:u\
       -e ref-cycles:u -e branch-instructions:u -e branch-misses:u ./main
 </source>

Pchero: Created page with "== Overview == 성능 분석 도구 perf 내용 정리 == perf stat == perf stat: obtain event counts === Options ===

 $ perf stat -h   usage: perf stat [] [
2016-05-04T09:02:15Z
Created page with "== Overview == 성능 분석 도구 perf 내용 정리  == perf stat == perf stat: obtain event counts  === Options === <pre> $ perf stat -h   usage: perf stat [<options>] [<c..."
New page
== Overview ==

성능 분석 도구 perf 내용 정리



== perf stat ==

perf stat: obtain event counts



=== Options ===

<pre>

$ perf stat -h



 usage: perf stat [<options>] [<command>]



    -T, --transaction     hardware transaction statistics

    -e, --event <event>   event selector. use 'perf list' to list available events

        --filter <filter>

                          event filter

    -i, --no-inherit      child tasks do not inherit counters

    -p, --pid <pid>       stat events on existing process id

    -t, --tid <tid>       stat events on existing thread id

    -a, --all-cpus        system-wide collection from all CPUs

    -g, --group           put the counters into a counter group

    -c, --scale           scale/normalize counters

    -v, --verbose         be more verbose (show counter open errors, etc)

    -r, --repeat <n>      repeat command and print average + stddev (max: 100, forever: 0)

    -n, --null            null run - dont start any counters

    -d, --detailed        detailed run - start a lot of events

    -S, --sync            call sync() before starting a run

    -B, --big-num         print large numbers with thousands' separators

    -C, --cpu <cpu>       list of cpus to monitor in system-wide

    -A, --no-aggr         disable CPU count aggregation

    -x, --field-separator <separator>

                          print counts with custom separator

    -G, --cgroup <name>   monitor event in cgroup name only

    -o, --output <file>   output file name

        --append          append to the output file

        --log-fd <n>      log output to fd, instead of stderr

        --pre <command>   command to run prior to the measured command

        --post <command>  command to run after to the measured command

    -I, --interval-print <n>

                          print counts at regular interval in ms (>= 100)

        --per-socket      aggregate counts per processor socket

        --per-core        aggregate counts per physical processor core

    -D, --delay <n>       ms to wait before starting measurement after program start

</pre>



=== Example ===

<source lang=bash>

$ perf stat --repeat 10 -e cycles:u -e instructions:u -e cache-references:u\

     -e cache-misses:u -e stalled-cycles-frontend:u -e stalled-cycles-backend:u\

     -e ref-cycles:u -e branch-instructions:u -e branch-misses:u ./main

</source>



== perf record ==

perf record: record events for later reporting



=== Options ===

<pre>

$ perf record -h



 usage: perf record [<options>] [<command>]

    or: perf record [<options>] -- <command> [<options>]



    -e, --event <event>   event selector. use 'perf list' to list available events

        --filter <filter>

                          event filter

    -p, --pid <pid>       record events on existing process id

    -t, --tid <tid>       record events on existing thread id

    -r, --realtime <n>    collect data with this RT SCHED_FIFO priority

    -D, --no-delay        collect data without buffering

    -R, --raw-samples     collect raw sample records from all opened counters

    -a, --all-cpus        system-wide collection from all CPUs

    -C, --cpu <cpu>       list of cpus to monitor

    -c, --count <n>       event period to sample

    -o, --output <file>   output file name

    -i, --no-inherit      child tasks do not inherit counters

    -F, --freq <n>        profile at this frequency

    -m, --mmap-pages <pages>

                          number of mmap data pages

        --group           put the counters into a counter group

    -g                    enables call-graph recording

        --call-graph <mode[,dump_size]>

                          setup and enables call-graph (stack chain/backtrace) recording: fp dwarf

    -v, --verbose         be more verbose (show counter open errors, etc)

    -q, --quiet           don't print any message

    -s, --stat            per thread counts

    -d, --data            Sample addresses

    -T, --timestamp       Sample timestamps

    -P, --period          Sample period

    -n, --no-samples      don't sample

    -N, --no-buildid-cache

                          do not update the buildid cache

    -B, --no-buildid      do not collect buildids in perf.data

    -G, --cgroup <name>   monitor event in cgroup name only

    -u, --uid <user>      user to profile

    -b, --branch-any      sample any taken branches

    -j, --branch-filter <branch filter mask>

                          branch stack filter modes

    -W, --weight          sample by weight (on special events only)

        --transaction     sample transaction flags (special events only)

        --force-per-cpu   force the use of per-cpu mmaps

</pre>



== perf report ==

perf report: break down events by process, function, etc.



== perf annotate ==

perf annotate: annotate assembly or source code with event counts



== perf top ==

perf top: see live event count



== perf bench ==

perf bench: run different kernel microbenchmarks 



== See also ==

* https://kldp.org/node/155216 - 최적화 도중에 난제를 만났습니다.(지역성 관련)

* https://perf.wiki.kernel.org/index.php/Main_Page - perf: Linux profiling with performance counters 



[[category:linux]]