From mboxrd@z Thu Jan  1 00:00:00 1970
From: "H. Peter Anvin" <hpa@zytor.com>
Subject: Re: [PATCH 12/22] virtio_pci: allow duplicate capabilities.
Date: Thu, 21 Mar 2013 10:09:02 -0700
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References: <20130321144330.GA1454@redhat.com> <514B1D25.9090206@zytor.com>
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To: "Michael S. Tsirkin" <mst@redhat.com>
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On 03/21/2013 10:07 AM, Michael S. Tsirkin wrote:
> 
> I just think it does not apply to BIOS so much.  A bigger issue for BIOS
> virtio performance is that it normally does not implement batching at
> all, to keep it simple and reduce memory usage it uses a small number
> (often 1) of outstanding buffers per queue.
> 

You asked for examples, so I gave one.  There is no doubt that BIOS can
make use of this if available.

What you describe above is of course a typical problem with BIOS.

	-hpa