From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Michael S. Tsirkin" <mst@redhat.com>
Subject: Re: [PATCH] virtio: Use ioeventfd for virtqueue notify
Date: Sun, 3 Oct 2010 16:28:28 +0200
Message-ID: <20101003142828.GB19775@redhat.com>
References: <1285855312-11739-1-git-send-email-stefanha@linux.vnet.ibm.com>
 <4CA862A7.2080302@redhat.com>
 <20101003135138.GA19775@redhat.com>
 <4CA89185.6070302@redhat.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
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: Avi Kivity <avi@redhat.com>
Return-path: <kvm-owner@vger.kernel.org>
Received: from mx1.redhat.com ([209.132.183.28]:8757 "EHLO mx1.redhat.com"
	rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP
	id S1751454Ab0JCOej (ORCPT <rfc822;kvm@vger.kernel.org>);
	Sun, 3 Oct 2010 10:34:39 -0400
Content-Disposition: inline
In-Reply-To: <4CA89185.6070302@redhat.com>
Sender: kvm-owner@vger.kernel.org
List-ID: <kvm.vger.kernel.org>

On Sun, Oct 03, 2010 at 04:21:57PM +0200, Avi Kivity wrote:
>  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.

Sorry, I meant irqfd.

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