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Date: Fri, 25 Mar 2011 11:31:38 +0100
From: Ingo Molnar <mingo@elte.hu>
To: Tejun Heo <tj@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>, Ingo Molnar <mingo@redhat.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
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Subject: Re: [PATCH 2/2] mutex: Apply adaptive spinning on mutex_trylock()
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* Tejun Heo <tj@kernel.org> wrote:

> Hello,
> 
> On Thu, Mar 24, 2011 at 10:41:51AM +0100, Tejun Heo wrote:
> >         USER   SYSTEM   SIRQ    CXTSW  THROUGHPUT
> >  SIMPLE 61107  354977    217  8099529  845.100 MB/sec
> >  SPIN   63140  364888    214  6840527  879.077 MB/sec
> > 
> > On various runs, the adaptive spinning trylock consistently posts
> > higher throughput.  The amount of difference varies but it outperforms
> > consistently.
> 
> I've been running more of these tests and am having doubts about the
> consistency.  It seems that, even on a fresh filesystem, some random
> initial condition seems to have persistent effect on the whole run.
> I'll run more tests and report back.

Ok, and there's the deadlock issue as well which Steve noticed.

I'll zap the patches from tip:core/urgent and lets do this via tip:core/locking 
with a .40 timeframe and plenty of time of testing.

Thanks,

	Ingo