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Date: Mon, 24 Sep 2012 14:30:04 +0200
From: Kevin Wolf <kwolf@redhat.com>
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Subject: Re: [Qemu-devel] linux aio and cache mode
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To: ching <lsching17@gmail.com>
Cc: qemu-devel@nongnu.org

Am 24.09.2012 13:32, schrieb ching:
> Hi all,
> 
> My host is qemu-1.1.1 and x64 kernel 3.5.4. The guest is using aio="native"
> 
> I am trying to use unsafe cache mode to boost i/o performance.

aio=native requires the image to be opened with O_DIRECT, i.e.
cache=none or cache=directsync. If you specify a different cache option,
it will silently fall back to aio=threads.

Kevin