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Date: Fri, 16 Sep 2016 19:54:21 -0400
From: "Emilio G. Cota" <cota@braap.org>
Message-ID: <20160916235421.GA18670@flamenco>
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Subject: Re: [Qemu-devel] [PATCH v4 26/35] tests: add atomic_add-bench
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To: Richard Henderson <rth@twiddle.net>
Cc: qemu-devel@nongnu.org

On Fri, Sep 16, 2016 at 10:46:48 -0700, Richard Henderson wrote:
> From: "Emilio G. Cota" <cota@braap.org>
> 
> With this microbenchmark we can measure the overhead of emulating atomic
> instructions with a configurable degree of contention.
> 
> The benchmark spawns $n threads, each performing $o atomic ops (additions)
> in a loop. Each atomic operation is performed on a different cache line
> (assuming lines are 64b long) that is randomly selected from a range [0, $r).
> 
> [ Note: each $foo corresponds to a -foo flag ]

Hi Richard,

As I mentioned yesterday I have an updated version of this
patch:  http://lists.gnu.org/archive/html/qemu-devel/2016-09/msg03450.html
[ The major change is to run for a certain number of seconds, instead
  of a fixed number of operations. ]

I'll send the full updated patch as a reply to this message to make
it easier to pick up.

Thanks,

		Emilio