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Date: Thu, 3 Apr 2008 12:38:34 +0100
From: Jamie Lokier <jamie@shareable.org>
Subject: Re: [Qemu-devel] [PATCH] Asynchronous reliable and configurable cache
	flush
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To: Ian Jackson <Ian.Jackson@eu.citrix.com>
Cc: Marcelo Tosatti <marcelo@kvack.org>, Paul Brook <paul@codesourcery.com>, qemu-devel@nongnu.org

Ian Jackson wrote:
> > > The cache is dynamically enabled/disabled by the target. This means
> > > you've got to close and repopen the file every time it changes,
> > > which is likely to get really hairy.
> > 
> > Just open two descriptors :-)
> 
> Doing it with bdrv_aio_flush wasn't too hard, so that's what'll be in
> my revised patch shortly.

For "uncached" writes, do you wait until _after_ the aio_write has
completed before calling aio_fsync, or do you assume the aio_fsync
will wait for all aio_writes queued (but not completed) prior to it,
as Marcelo Tosatti believes the documentation implies?

Thanks,
-- Jamie