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Date: Tue, 08 Jan 2013 21:23:12 +0800
From: Liu Yuan <namei.unix@gmail.com>
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Subject: Re: [Qemu-devel] [PATCH] sheepdog: implement direct write semantics
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To: Kevin Wolf <kwolf@redhat.com>
Cc: Stefan Hajnoczi <stefanha@gmail.com>, qemu-devel@nongnu.org, MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>, Paolo Bonzini <pbonzini@redhat.com>

On 01/08/2013 09:18 PM, Liu Yuan wrote:
> So the result is *not* broken. If we set cache=writethrough for
> sheepdog, then WCE won't take any effect because 'flush' request will be
> ignored by Sheepdog driver. 

The merit of this 'writethrough' is that, write request will never be
interpreted as two requests: write + flush in Sheepdog driver.

Thanks,
Yuan