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Date: Wed, 13 Jan 2016 11:25:02 +0100
From: Ingo Molnar <mingo@kernel.org>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>,
        Stephane Eranian <eranian@google.com>,
        Namhyung Kim <namhyung@gmail.com>, LKML <linux-kernel@vger.kernel.org>,
        Jiri Olsa <jolsa@kernel.org>, Namhyung Kim <namhyung@kernel.org>,
        Adrian Hunter <adrian.hunter@intel.com>,
        "ak@linux.intel.com" <ak@linux.intel.com>
Subject: Re: [RFC] perf record: missing buildid for callstack modules
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* Peter Zijlstra <peterz@infradead.org> wrote:

> On Tue, Jan 12, 2016 at 11:34:54AM -0300, Arnaldo Carvalho de Melo wrote:
>
> > Have you ever played, when you noticed those overheads, with -N? Or just used 
> > the -B big hammer and moved on?
> 
> I yelled on irc, jolsa told me to use -B, I moved on ;-)

So I think we should grow mtime protection, to not display incorrect data - and 
then that should become the default. (in addition to per CPU recording threads.)

Way too slow recording is something I experience as well - and to have a slow 
_performance_ profiling tool is pretty ironic! ;-)

Thanks,

	Ingo