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Date: Tue, 25 Dec 2012 16:45:55 +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: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
Cc: Kevin Wolf <kwolf@redhat.com>, Stefan Hajnoczi <stefanha@gmail.com>, qemu-devel@nongnu.org

On 12/25/2012 03:47 PM, MORITA Kazutaka wrote:
> I wonder if we should disable cache when cache=none.  Many management
> frontend uses cache=none by default but, I think, users still expect
> that data is cached (e.g. by disk write cache when a raw format is
> used).  cache=none only means that the host page cache is not used for
> VM disk IO.
> 
> In that sense,

Well, I found setting cache=directsync will contain 'BDRV_O_CACHE_WB'.
Is this a bug for current master? If no, my current scheme will be the
only way to bypass cache of sheepdog.

Thanks,
Yuan