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Date: Tue, 23 Sep 2008 20:04:50 +0200
From: Gerd Hoffmann <kraxel@redhat.com>
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Subject: Re: [Qemu-devel] Re: [PATCH 2/3] Move aio implementation out of raw
	block driver
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To: Anthony Liguori <aliguori@us.ibm.com>
Cc: Ryan Harper <ryanh@us.ibm.com>, qemu-devel@nongnu.org, kvm@vger.kernel.org, Marcelo Tosatti <mtosatti@redhat.com>

Anthony Liguori wrote:
> Gerd Hoffmann wrote:
>> How about providing a aio interface implementation which simply uses
>> read/write syscalls (thereby not being really async obviously)?  Then
>> use that as fallback instead of aio emulation?  And also drop CONFIG_AIO
>> then?
> 
> Yeah, this is basically what block-raw-posix does today.  I was thinking
> the same thing.  I was also thinking that you could do an aio
> implementation for win32 and possibly reunify block-raw-posix and
> block-raw-linux.

Sure, that the next logical steps.  Later we can also convert all
block-* drivers to the new aio interface and subsequently drop alot of
dead block layer code.

> But before going down this route, I want to see if linux-aio is really
> the right tool for the job.

IMHO this all makes sense even in case linux-aio turns out to not be
worth it.

cheers,
  Gerd