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Date: Wed, 29 Apr 2009 13:21:30 +0200
From: Christoph Hellwig <hch@lst.de>
Subject: Re: [Qemu-devel] Re: [PATCH] virtio-blk: add SGI_IO passthru support
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To: Paul Brook <paul@codesourcery.com>
Cc: kvm@vger.kernel.org, Rusty Russell <rusty@rustcorp.com.au>, qemu-devel@nongnu.org, Christian Borntraeger <borntraeger@de.ibm.com>, Hannes Reinecke <hare@suse.de>, Christoph Hellwig <hch@lst.de>

On Wed, Apr 29, 2009 at 12:11:19PM +0100, Paul Brook wrote:
> Is this actually measurably faster, or just infinitesimally faster in theory?

On normal disks it's rather theoretical.  On high-end SSDs and arrays the
impact is noticeable, mostly due to the additional latency.