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Date: Thu, 01 Jul 2010 10:29:04 +0300
From: Avi Kivity <avi@redhat.com>
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To: Alexander Graf <agraf@suse.de>
Subject: Re: [PATCH 0/2] Faster MMU lookups for Book3s v3
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On 06/30/2010 04:18 PM, Alexander Graf wrote:
> Book3s suffered from my really bad shadow MMU implementation so far. So
> I finally got around to implement a combined hash and list mechanism that
> allows for much faster lookup of mapped pages.
>
> To show that it really is faster, I tried to run simple process spawning
> code inside the guest with and without these patches:
>
> [without]
>
> debian-powerpc:~# time for i in {1..1000}; do /bin/echo hello>  /dev/null; done
>
> real    0m20.235s
> user    0m10.418s
> sys     0m9.766s
>
> [with]
>
> debian-powerpc:~# time for i in {1..1000}; do /bin/echo hello>  /dev/null; done
>
> real    0m14.659s
> user    0m8.967s
> sys     0m5.688s
>
> So as you can see, performance improved significantly.
>
> v2 ->  v3:
>
>    - use hlist
>    - use global slab cache
>
>    

Looks good.

-- 
I have a truly marvellous patch that fixes the bug which this
signature is too narrow to contain.