From mboxrd@z Thu Jan  1 00:00:00 1970
From: Avi Kivity <avi@redhat.com>
Subject: Re: [PATCH] virtio: Use ioeventfd for virtqueue notify
Date: Sun, 03 Oct 2010 16:21:57 +0200
Message-ID: <4CA89185.6070302@redhat.com>
References: <1285855312-11739-1-git-send-email-stefanha@linux.vnet.ibm.com> <4CA862A7.2080302@redhat.com> <20101003135138.GA19775@redhat.com>
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Cc: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>,
	qemu-devel@nongnu.org, kvm@vger.kernel.org,
	Anthony Liguori <aliguori@us.ibm.com>,
	Khoa Huynh <khoa@us.ibm.com>,
	Sridhar Samudrala <sri@us.ibm.com>,
	Steve Dobbelstein <steved@us.ibm.com>
To: "Michael S. Tsirkin" <mst@redhat.com>
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  On 10/03/2010 03:51 PM, Michael S. Tsirkin wrote:
> On Sun, Oct 03, 2010 at 01:01:59PM +0200, Avi Kivity wrote:
> >  >
> >  >Guest to Host TCP_STREAM throughput(Mb/sec)
> >  >-------------------------------------------
> >  >Msg Size  vhost-net  virtio-net  virtio-net/ioeventfd
> >  >65536         12755        6430                  7590
> >  >16384          8499        3084                  5764
> >  >   4096          4723        1578                  3659
> >  >   1024          1827         981                  2060
> >
> >  Even more impressive (expected since the copying, which isn't
> >  present for block, is now shunted off into an iothread).
> >
> >  On the last test you even exceeded vhost-net.  Any theories how/why?
> >
> >  Again, efficiency numbers would be interesting.
> >
> >  >Host to Guest TCP_STREAM throughput(Mb/sec)
> >  >-------------------------------------------
> >  >Msg Size  vhost-net  virtio-net  virtio-net/ioeventfd
> >  >65536         11156        5790                  5853
> >  >16384         10787        5575                  5691
> >  >   4096         10452        5556                  4277
> >  >   1024          4437        3671                  5277
> >
> >  Here you exceed vhost-net, too.
>
> This is with small packets- I suspect this is the extra
> per interrupt overhead  that eventfd has.

This is using eventfd as well.

-- 
error compiling committee.c: too many arguments to function