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Subject: Re: [GIT PULL 00/10] perf/core improvements and fixes
To: Brendan Gregg <bgregg@netflix.com>, Namhyung Kim <namhyung@kernel.org>
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From: Paolo Bonzini <pbonzini@redhat.com>
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Date: Tue, 21 Jun 2016 12:08:47 +0200
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On 21/06/2016 05:11, Brendan Gregg wrote:
>>> > > - Add stackcollapse.py script to help generating flame graphs (Paolo Bonzini)
>> >
>> > I think this is already done by '-g folded'.  Please see:
>> >
>> >   http://www.brendangregg.com/blog/2016-04-30/linux-perf-folded.html
>> >
> Pretty much. Two similar solutions were developed around the same
> time. Although I have to use some awk to get "perf -g folded" in the
> exact right format, and stackcollapse-perf.py does that directly.

Yes, the idea for stackcollapse-perf.py was:

- to do everything directly and emit "the right" format for the
flamegraph tools.  This however is a very minimal output, and it's not
necessarily the best for perf in general.

- to provide an example of visiting callgraphs from the scripting
interface, since it's not really documented.  From the commit message:
"Add stackcollapse.py script as an example of parsing call chains, and
also of using optparse to access command line options".

Paolo