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Date:   Fri, 15 Jun 2018 10:12:23 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     "Jin, Yao" <yao.jin@linux.intel.com>
Cc:     acme@kernel.org, jolsa@kernel.org, mingo@redhat.com,
        alexander.shishkin@linux.intel.com, me@kylehuey.com,
        Linux-kernel@vger.kernel.org, vincent.weaver@maine.edu,
        will.deacon@arm.com, eranian@google.com, namhyung@kernel.org,
        ak@linux.intel.com, kan.liang@intel.com, yao.jin@intel.com
Subject: Re: [PATCH v1 0/2] perf: Drop leaked kernel samples
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On Fri, Jun 15, 2018 at 04:01:45PM +0800, Jin, Yao wrote:

> Bring more overhead to kernel if we zero the bits considering the number of
> leaked samples may be not too small?

Keeping the samples at least allows you to know how many samples
happened and such things.

> And the skid information may be interesting (see example of hitting on
> page_fault in previous mail). If we zero it, we will not know.

If you throw them out the window you also don't know, do you?