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Date: Mon, 5 Dec 2011 12:16:57 -0800
From: Arun Sharma <asharma@fb.com>
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To: Stephane Eranian <eranian@google.com>
CC: Peter Zijlstra <a.p.zijlstra@chello.nl>, <mingo@elte.hu>,
        William Cohen <wcohen@redhat.com>, Vince Weaver <vince@deater.net>,
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Subject: Re: [RFC][PATCH 0/6] perf: x86 RDPMC and RDTSC support
References: <20111121145114.049265181@chello.nl> <4ED9267F.10106@fb.com> <CABPqkBRpYA-StOTDFwyFhFtBPynbn-FLUzqZvaQn3oM3SJpCWg@mail.gmail.com>
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On 12/2/11 2:22 PM, Stephane Eranian wrote:
> Have you tried with inheritance disabled?
> I don't remember if perf stat has it enabled buy default.

Disabling inheritance using the -i switch as in:

(for i in `seq 1 10`; do numactl --cpunodebind 1 perf stat -i -e 
instructions ./lat_ctx -P1 -s32k 4; done)

shows numbers closer to baseline, since the threads used for 
benchmarking are not counting events.

This suggests that:

jump_label_dec(&perf_task_events);

itself doesn't hurt much.

  -Arun