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Date: Wed, 21 Oct 2015 10:21:22 -0300
From: Arnaldo Carvalho de Melo <arnaldo.melo@gmail.com>
To: Ingo Molnar <mingo@kernel.org>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Adrian Hunter <adrian.hunter@intel.com>, Borislav Petkov <bp@suse.de>,
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        Namhyung Kim <namhyung@kernel.org>,
        Stephane Eranian <eranian@google.com>, Wang Nan <wangnan0@huawei.com>
Subject: Re: [PATCH 13/16] perf callchain: Switch default to
 'graph,0.5,caller'
Message-ID: <20151021132122.GD10639@kernel.org>
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Em Wed, Oct 21, 2015 at 10:06:45AM +0200, Ingo Molnar escreveu:
> * Arnaldo Carvalho de Melo <arnaldo.melo@gmail.com> wrote:
> > Indeed, finding a default that is deemed adequate for most people is, ho-hum, 
> > difficult 8-)

> > Ingo, what do you think?
 
> So I think the new default is a lot more intuitive, because it starts with a high 
> level top-down 'overview' kind of output, allowing one to drill down to the 
> details.
 
> That's what most other tools do as well by default, and people migrating to perf 
> found it pretty confusing that we do a bottom-up kind of callgraph.
 
> To people using perf for the first time it does not matter nearly as much, but 
> intuitiveness is still a factor.
 
> The new default requires good call-chains and good symbol resolution to be 
> maximally effective, but we want perfect callchains and symbols in any case, 
> right?

Sure, but in hindsight, we could've fixed those problems before flipping
the switch :-)

And also we didn't care about it that much because for callee based
callchains they are far from the focus point.

- Arnaldo