From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Hellwig <hch@lst.de>
Subject: Re: [Qemu-devel] Re: [PATCH] virtio-blk: add SGI_IO passthru support
Date: Wed, 29 Apr 2009 13:21:30 +0200
Message-ID: <20090429112130.GA11241@lst.de>
References: <20090427082606.GA32604@lst.de> <49F730AD.8090705@codemonkey.ws> <20090429104854.GA7846@lst.de> <200904291211.20374.paul@codesourcery.com>
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Cc: qemu-devel@nongnu.org, Christoph Hellwig <hch@lst.de>,
	Anthony Liguori <anthony@codemonkey.ws>, kvm@vger.kernel.org,
	Rusty Russell <rusty@rustcorp.com.au>,
	Christian Borntraeger <borntraeger@de.ibm.com>,
	Hannes Reinecke <hare@suse.de>
To: Paul Brook <paul@codesourcery.com>
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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.