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For those put off by the baroque interface and daunting learning curve of [[Oprofile]], Ingo | For those put off by the baroque interface and daunting learning curve of [[Oprofile]], Ingo Molnár's perf tool (included with the linux kernel since at least version 2.6.30 in <tt>tools/perf</tt>) is a quick and easy way to get data from x86's [[Performance Counters|performance counters]]. | ||
You need to have <tt>CONFIG_LOCKDEP</tt> and <tt>CONFIG_LOCK_STAT</tt> enabled to use <tt>perf lock</tt>. | |||
==perf stat== | |||
* <tt>-r num</tt> can be used to run the pass <tt>num</tt> times, displaying a standard deviation: | |||
<pre> | |||
Performance counter stats for './notcurses-demo -k -c ww' (3 runs): | |||
23,153,745,413 cycles ( +- 0.64% ) | |||
67,109,369,279 instructions # 2.90 insn per cycle ( +- 0.35% ) | |||
86,574,323 cache-misses ( +- 1.79% ) | |||
10,555,354,499 branches ( +- 0.35% ) | |||
11.0698 +- 0.0119 seconds time elapsed ( +- 0.11% ) | |||
</pre> | |||
==See Also== | ==See Also== | ||
* 2009-06-06 [http://lkml.org/lkml/2009/6/6/149 LKML post] announcing version -v8 | * 2009-06-06 [http://lkml.org/lkml/2009/6/6/149 LKML post] announcing version -v8 | ||
Latest revision as of 10:25, 28 January 2022
For those put off by the baroque interface and daunting learning curve of Oprofile, Ingo Molnár's perf tool (included with the linux kernel since at least version 2.6.30 in tools/perf) is a quick and easy way to get data from x86's performance counters.
You need to have CONFIG_LOCKDEP and CONFIG_LOCK_STAT enabled to use perf lock.
perf stat
- -r num can be used to run the pass num times, displaying a standard deviation:
Performance counter stats for './notcurses-demo -k -c ww' (3 runs):
23,153,745,413 cycles ( +- 0.64% )
67,109,369,279 instructions # 2.90 insn per cycle ( +- 0.35% )
86,574,323 cache-misses ( +- 1.79% )
10,555,354,499 branches ( +- 0.35% )
11.0698 +- 0.0119 seconds time elapsed ( +- 0.11% )
See Also
- 2009-06-06 LKML post announcing version -v8
