Date: Mon, 14 Dec 2015 10:12:21 +0900
From: Namhyung Kim <namhyung@kernel.org>
To: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>, Arnaldo Carvalho de Melo <acme@kernel.org>,
        Peter Zijlstra <a.p.zijlstra@chello.nl>, Jiri Olsa <jolsa@redhat.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Frederic Weisbecker <fweisbec@gmail.com>,
        Andi Kleen <andi@firstfloor.org>,
        Stephane Eranian <eranian@google.com>,
        Adrian Hunter <adrian.hunter@intel.com>
Subject: Re: [PATCHSET 00/16] perf top: Add multi-thread support (v1)
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Hi David and Ingo,

On Fri, Dec 11, 2015 at 08:01:31AM -0700, David Ahern wrote:
> On 12/11/15 1:11 AM, Ingo Molnar wrote:
> >
> >* Namhyung Kim <namhyung@gmail.com> wrote:
> >
> >>IIRC David said that thread per cpu seems too much especially on a large system
> >>(like ~1024 cpu). [...]
> >
> >Too much in what fashion? For recording I think it's the fastest, most natural
> >model - anything else will create cache line bounces.
> 
> The intrusiveness of perf on the system under observation. I understand
> there are a lot of factors that go into it.

So what would be the sane default?  Do you have any other suggestion?

If there's no opinion, I'll follow Ingo's..

Thanks,
Namhyung
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