From: Rusty Russell <rusty@rustcorp.com.au>
Subject: Re: [PATCH] virtio-blk: set QUEUE_ORDERED_DRAIN by default
Date: Tue, 25 Aug 2009 23:41:37 +0930
Message-ID: <200908252341.38356.rusty@rustcorp.com.au>
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Cc: borntraeger@de.ibm.com, linux-kernel@vger.kernel.org,
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To: Christoph Hellwig <hch@lst.de>
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On Fri, 21 Aug 2009 06:26:16 am Christoph Hellwig wrote:
> Currently virtio-blk doesn't set any QUEUE_ORDERED_ flag by default, which
> means it does not allow filesystems to use barriers.  But the typical use
> case for virtio-blk is to use a backed that uses synchronous I/O

Really?  Does qemu open with O_SYNC?

I'm definitely no block expert, but this seems strange...
Rusty.