From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Hellwig <hch@infradead.org>
Subject: Re: linux-aio usable?
Date: Mon, 8 Mar 2010 08:00:21 -0500
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Cc: Bernhard Schmidt <berni@birkenwald.de>, kvm@vger.kernel.org
To: Avi Kivity <avi@redhat.com>
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On Mon, Mar 08, 2010 at 11:10:29AM +0200, Avi Kivity wrote:
>> Are there any potential pitfalls?
>>    
>
> It won't work well unless running on a block device (partition or LVM).

It will actually work well on pre-allocated filesystem images, at least
on XFS and NFS.

The real pitfal is that cache=none is required for kernel support as
it only supports O_DIRECT.

>> Is there any reason one should not compile that feature by default?

It's compiled by default if libaio and it's development headers are
found.

>> Does it do anything if not explicitly run with aio=native?

No.