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Date: Fri, 18 Apr 2014 09:55:25 +0200
From: Ingo Molnar <mingo@kernel.org>
To: Jiri Olsa <jolsa@redhat.com>
Cc: linux-kernel@vger.kernel.org, Corey Ashford <cjashfor@linux.vnet.ibm.com>,
        David Ahern <dsahern@gmail.com>,
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        Namhyung Kim <namhyung@kernel.org>, Paul Mackerras <paulus@samba.org>,
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        Arnaldo Carvalho de Melo <acme@ghostprotocols.net>,
        Jean Pihet <jean.pihet@linaro.org>
Subject: Re: [PATCH 0/3] perf tools: Speedup DWARF unwind
Message-ID: <20140418075525.GA14243@gmail.com>
References: <1397756352-26694-1-git-send-email-jolsa@redhat.com>
 <20140418075148.GA13793@gmail.com>
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* Ingo Molnar <mingo@kernel.org> wrote:

> 
> * Jiri Olsa <jolsa@redhat.com> wrote:
> 
> > hi,
> > trying to speedup DWARF unwind report code by factoring
> > related code:
> >   - caching sample's registers access
> >   - keep dso data file descriptor open for the
> >     life of the dso object
> >   - replace dso cache code by mapping dso data file
> >     directly for the life of the dso object
> > 
> > The speedup is mainly for libunwind unwind. The libdw will benefit
> > mainly from cached registers access, because it handles dso data
> > accesses by itself.. and anyway it's still faster ;-).
> 
> Just curious: do you have any numbers about how much faster it got in 
> practice?

Oh, the numbers are all in the changelogs, never mind!

So in your test workload it went from 54.6 seconds to 36.7, a 48% 
speedup :-)

Thanks,

	Ingo