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Date: Tue, 25 Jul 2006 22:37:56 +0200
From: Fabrice Bellard <fabrice@bellard.org>
Subject: Re: [Qemu-devel] Re: high CPU load / async IO?
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To: qemu-devel@nongnu.org

Jens Axboe wrote:
> On Tue, Jul 25 2006, Sven K=F6hler wrote:
>=20
>>>>>So the current thread-based async dma patch is really just the w=
rong long
>>>>>term solution.  A more long term solution is likely in the works=
.  It
>>>>>requires quite a bit of code modification though.
>>>>
>>>>I see. So in other words:
>>>>
>>>>don't ask for simple async I/O now. The more complex and flexible
>>>>sollution will follow soon.
>>>
>>>Yes, hopefully really soon.
>>
>>So i will wait patiently :-)
>=20
>=20
> Is anyone actively working on this, or is it just speculation? I'd
> greatly prefer (and might do, if no one is working on it and Fabric=
e
> would take it) do a libaio version, since that'll for sure perform =
the
> best on Linux. But a posixaio version might be saner, as that shoul=
d
> work on other operating systems as well.
>=20
> Fabrice, can you let people know what you would prefer?

I am working on an implementation and the first version will use the=
=20
posix aio and possibly the Windows ReadFile/WriteFile overlapped I/Os=
.=20
Anthony Liguori got a pre version of the code, but it is not commitab=
le yet.

Fabrice.