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Subject: Re: [PATCH 0/3] FUTEX : new PRIVATE futexes, SMP and NUMA
	improvements
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Eric Dumazet <dada1@cosmosbay.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>, Ulrich Drepper <drepper@gmail.com>,
       Andrew Morton <akpm@linux-foundation.org>, Ingo Molnar <mingo@elte.hu>,
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       "Shai Fultheim (Shai@scalex86.org)" <shai@scalex86.org>,
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Date: Fri, 16 Mar 2007 09:05:41 +0100
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On Thu, 2007-03-15 at 20:10 +0100, Eric Dumazet wrote:
> Hi
> 
> I'm pleased to present these patches which improve linux futex performance and 
> scalability, on both UP, SMP and NUMA configs.
> 
> I had this idea last year but I was not understood, probably because I gave 
> not enough explanations. Sorry if this mail is really long...

I started playing with it after your last reference to it, I have some
code here (against -rt):
  http://programming.kicks-ass.net/kernel-patches/futex-vma-cache/

Which I will post once I have the found what keeps pthread_join() from
completing :-(

It basically adds a per task vma lookup cache which can also activate
the private logic without explicit use of the new interface.