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Date: Wed, 21 Nov 2012 10:34:31 +0100
From: Ingo Molnar <mingo@kernel.org>
To: David Rientjes <rientjes@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
        Mel Gorman <mgorman@suse.de>,
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        Thomas Gleixner <tglx@linutronix.de>,
        Johannes Weiner <hannes@cmpxchg.org>, Hugh Dickins <hughd@google.com>
Subject: Re: [PATCH, v2] mm, numa: Turn 4K pte NUMA faults into effective
 hugepage ones
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* David Rientjes <rientjes@google.com> wrote:

> Ok, this is significantly better, it almost cut the regression 
> in half on my system. [...]

The other half still seems to be related to the emulation faults 
that I fixed in the other patch:

>      0.49%  [kernel]          [k] page_fault                                               
>      0.06%  [kernel]          [k] emulate_vsyscall                                         

Plus TLB flush costs:

>      0.13%  [kernel]          [k] generic_smp_call_function_interrupt
>      0.08%  [kernel]          [k] flush_tlb_func

for which you should try the third patch I sent.

So please try all my fixes - the easiest way to do that would be 
to try the latest tip:master that has all related fixes 
integrated and send me a new perf top output - most page fault 
and TLB flush overhead should be gone from the profile.

Thanks,

	Ingo