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Re: [RFC/PATCH 10/10] perf tools: Change default calchain percent limit to 0.005%

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On Thu, Jan 28, 2016 at 12:40:57AM +0900, Namhyung Kim wrote:
> The current default limit of 0.5% is (mostly) for 'fractal' mode which
> calculates the percentage relatively.  As we changed the default
> callchain mode to 'graph', the existing limit is too high IMHO.
> Normally there're many entries under 0.5% overhead, it'd be supprising
> that they don't show callchains.

It's too small imho. On more complex workloads with a lot of user space
code we often end up with default perf report --stdio callgraph output of several
hundred KB, and most of it is useless as it is only very small.

-Andi

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[PATCHSET 00/10] perf tools: Apply percent-limit to callchains (v2) Namhyung Kim <namhyung@kernel.org> - 2016-01-27 16:50 +0100
  [PATCH 07/10] perf hists browser: Fix dump to show correct callchain style Namhyung Kim <namhyung@kernel.org> - 2016-01-27 16:50 +0100
  [PATCH 09/10] perf hists browser: Fix percent display in callchains Namhyung Kim <namhyung@kernel.org> - 2016-01-27 16:50 +0100
  [PATCH 04/10] perf report: Get rid of hist_entry__callchain_fprintf() Namhyung Kim <namhyung@kernel.org> - 2016-01-27 16:50 +0100
  [PATCH 01/10] perf hists: Fix min callchain hits calculation Namhyung Kim <namhyung@kernel.org> - 2016-01-27 16:50 +0100
  [PATCH 03/10] perf report: Apply --percent-limit to callchains also Namhyung Kim <namhyung@kernel.org> - 2016-01-27 16:50 +0100
  [PATCH 06/10] perf report: Fix percent display in callchains on --stdio Namhyung Kim <namhyung@kernel.org> - 2016-01-27 16:50 +0100
  [RFC/PATCH 10/10] perf tools: Change default calchain percent limit to 0.005% Namhyung Kim <namhyung@kernel.org> - 2016-01-27 16:50 +0100
    Re: [RFC/PATCH 10/10] perf tools: Change default calchain percent  limit to 0.005% Andi Kleen <andi@firstfloor.org> - 2016-01-27 17:10 +0100

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