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Date: Fri, 18 Apr 2008 19:32:16 +0300
From: Avi Kivity <avi@qumranet.com>
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Subject: Re: [kvm-devel] [Qemu-devel] Re: [PATCH 1/3] Refactor AIO interface
	to allow other AIO implementations
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To: Anthony Liguori <aliguori@us.ibm.com>
Cc: kvm-devel@lists.sourceforge.net, Marcelo Tosatti <mtosatti@redhat.com>, qemu-devel@nongnu.org

Anthony Liguori wrote:
> Right now, not specifying the -aio option is equivalent to your proposed 
> -aio auto.
>
> I guess I should include an info aio to let the user know what type of 
> aio they are using.  We can add selection criteria later but 
> semantically, not specifying an explicit -aio option allows QEMU to 
> choose whichever one it thinks is best.
>
>   
For the majority of deployments posix aio should be sufficient.  The few 
that need something else can use Linux aio.

Of course, a managed environment can use Linux aio unconditionally if 
knows the kernel has all the needed goodies.

-- 
Any sufficiently difficult bug is indistinguishable from a feature.