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Re: 'perf stat --repeat N' oddity/regression

From Ingo Molnar <mingo@kernel.org>
Newsgroups linux.kernel
Subject Re: 'perf stat --repeat N' oddity/regression
Date 2016-01-25 19:40 +0100
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So it appears it broke somewhere between v4.0 and v4.1, as the v4.0 install 
displays:

    16,244,802,268      instructions               ( +- 23.01% )

       2.108676769 seconds time elapsed                                          ( +-  0.86% )


[a few minutes later]

Bisected it down to:

 106a94a0f8c207ef4113ce7e32f34a00b3b174e7 is the first bad commit
 commit 106a94a0f8c207ef4113ce7e32f34a00b3b174e7
 Author: Jiri Olsa <jolsa@kernel.org>
 Date:   Fri Jun 26 11:29:19 2015 +0200

     perf stat: Introduce read_counters function

So this look like to be a regression.

Thanks,

	Ingo

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'perf stat --repeat N' oddity/regression Ingo Molnar <mingo@kernel.org> - 2016-01-25 19:30 +0100
  Re: 'perf stat --repeat N' oddity/regression Ingo Molnar <mingo@kernel.org> - 2016-01-25 19:40 +0100
    Re: 'perf stat --repeat N' oddity/regression Arnaldo Carvalho de Melo <acme@kernel.org> - 2016-01-25 20:50 +0100
      Re: 'perf stat --repeat N' oddity/regression Ingo Molnar <mingo@kernel.org> - 2016-01-26 09:10 +0100
        Re: 'perf stat --repeat N' oddity/regression Arnaldo Carvalho de Melo <acme@kernel.org> - 2016-01-26 15:20 +0100
    Re: 'perf stat --repeat N' oddity/regression Arnaldo Carvalho de Melo <acme@kernel.org> - 2016-01-25 20:50 +0100

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