Subject: Re: [PATCHSET 00/16] perf top: Add multi-thread support (v1)
To: Ingo Molnar <mingo@kernel.org>, Namhyung Kim <namhyung@gmail.com>
References: <1449734015-9148-1-git-send-email-namhyung@kernel.org>
 <20151210080118.GA8664@gmail.com>
 <5E6F0F13-9696-45F1-A0E8-CA0B95020D10@gmail.com>
 <20151211081141.GA21600@gmail.com>
Cc: Namhyung Kim <namhyung@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>
From: David Ahern <dsahern@gmail.com>
Message-ID: <566AE54B.1010702@gmail.com>
Date: Fri, 11 Dec 2015 08:01:31 -0700
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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.
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