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Date: Wed, 21 Oct 2015 10:06:45 +0200
From: Ingo Molnar <mingo@kernel.org>
To: Arnaldo Carvalho de Melo <arnaldo.melo@gmail.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>,
        LKML <linux-kernel@vger.kernel.org>,
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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: <20151021080645.GA9318@gmail.com>
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* 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?

Thanks,

	Ingo