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Date: Mon, 11 May 2015 17:44:05 +0200
From: Andi Kleen <andi@firstfloor.org>
To: Namhyung Kim <namhyung@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>, Ingo Molnar <mingo@kernel.org>,
        Peter Zijlstra <a.p.zijlstra@chello.nl>, Jiri Olsa <jolsa@redhat.com>,
        LKML <linux-kernel@vger.kernel.org>, David Ahern <dsahern@gmail.com>,
        Stephane Eranian <eranian@google.com>,
        Andi Kleen <andi@firstfloor.org>, Minchan Kim <minchan@kernel.org>
Subject: Re: [RFC/PATCH v2] perf data: Add stat subcommand to show sample
 event stat
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> The sampling ratio was useful for me to determine how often the event
> was sampled - in this case the cpu cycles event was only sampled at 12%

That's dangerous to determine without a plot. It could be that it was bimodal: 
100% busy and then idle. You may want to add something like the spark
plots I submitted for stat some time ago.

-Andi