RE: [PATCH 0/3]measure SMI cost

From	"Liang, Kan" <kan.liang@intel.com>
Newsgroups	linux.kernel
Subject	RE: [PATCH 0/3]measure SMI cost
Date	2017-03-24 15:20 +0100
Message-ID	<toyem-2LK-41@gated-at.bofh.it> (permalink)
References	<tofOp-6a9-23@gated-at.bofh.it> <tot4Z-7ku-1@gated-at.bofh.it> <tovTb-VO-15@gated-at.bofh.it> <towcx-1kb-1@gated-at.bofh.it>
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> 
> > > > A new --smi-cost mode in perf stat is implemented to measure the
> > > > SMI cost by calculating cycles and aperf results. In practice, the
> > > > percentages of SMI cycles should be more useful than absolute value.
> > >
> > > That's only true for performance oriented analysis, but for
> > > analyzing the root cause of latencies the actual cycles are definitely
> interesting.
> >
> > perf stat also prints the absolute cycles of course (unless you do
> > --metric-only)
> 
> So much for the theory. From the patch:
> 
> +                       if (!force_metric_only)
> +                               metric_only = true;
> 

The metric_only will be set by default in the patch. If user wants to get
the actual cycles, they can apply --no-metric-only. 

Do you want me to make it clear in the changelog? Or you just don't like
that "metric_only=true" is set by default?


Thanks,
Kan

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[PATCH 0/3]measure SMI cost kan.liang@intel.com - 2017-03-23 19:40 +0100
  [PATCH 1/3] perf/x86: add sysfs entry to freeze counter on SMI kan.liang@intel.com - 2017-03-23 19:40 +0100
    Re: [PATCH 1/3] perf/x86: add sysfs entry to freeze counter on SMI Peter Zijlstra <peterz@infradead.org> - 2017-03-23 21:40 +0100
      Re: [PATCH 1/3] perf/x86: add sysfs entry to freeze counter on SMI Thomas Gleixner <tglx@linutronix.de> - 2017-03-24 09:40 +0100
        RE: [PATCH 1/3] perf/x86: add sysfs entry to freeze counter on SMI "Liang, Kan" <kan.liang@intel.com> - 2017-03-24 15:20 +0100
          Re: [PATCH 1/3] perf/x86: add sysfs entry to freeze counter on SMI Peter Zijlstra <peterz@infradead.org> - 2017-03-24 15:30 +0100
    Re: [PATCH 1/3] perf/x86: add sysfs entry to freeze counter on SMI Peter Zijlstra <peterz@infradead.org> - 2017-03-23 21:40 +0100
      RE: [PATCH 1/3] perf/x86: add sysfs entry to freeze counter on SMI "Liang, Kan" <kan.liang@intel.com> - 2017-03-23 21:50 +0100
      Re: [PATCH 1/3] perf/x86: add sysfs entry to freeze counter on SMI Andi Kleen <ak@linux.intel.com> - 2017-03-23 23:30 +0100
        Re: [PATCH 1/3] perf/x86: add sysfs entry to freeze counter on SMI Peter Zijlstra <peterz@infradead.org> - 2017-03-24 09:20 +0100
  [PATCH 3/3] perf stat: Add support to measure SMI cost kan.liang@intel.com - 2017-03-23 19:40 +0100
  Re: [PATCH 0/3]measure SMI cost Thomas Gleixner <tglx@linutronix.de> - 2017-03-24 09:50 +0100
    Re: [PATCH 0/3]measure SMI cost Andi Kleen <ak@linux.intel.com> - 2017-03-24 12:50 +0100
      Re: [PATCH 0/3]measure SMI cost Thomas Gleixner <tglx@linutronix.de> - 2017-03-24 13:10 +0100
        RE: [PATCH 0/3]measure SMI cost "Liang, Kan" <kan.liang@intel.com> - 2017-03-24 15:20 +0100

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