Re: Virtio network performance poorer than emulated e1000

Balachandar
2010-07-26T14:39:41Z

On Mon, Jul 26, 2010 at 9:44 AM, Michael Tokarev <mjt@tls.msk.ru> wrote:
> 26.07.2010 11:26, Jes Sorensen wrote:
>>
>> On 07/24/10 17:04, Balachandar wrote:
>>>
>>> On Fri, Jul 23, 2010 at 3:11 AM, Jes Sorensen<Jes.Sorensen@redhat.com>
>>>  wrote:
>>> Actually i got better results when i downloaded qemu-kvm 0.12.4 from
>>> sourceforge and ran it. Now virtio performs better than emaulated
>>> e1000 with our own simple ping-pong latency tests. Previously i used
>>> Debian squeeze kvm package and i got poor results for virtio. I used
>>> vhost-net as described by the kvm
>>> website.http://www.linux-kvm.org/page/VhostNet. This also seem to have
>>> the same problems i faced with Debian kvm package. How are you guyz
>>> using vhost? Is there any other way to use vhost?
>>
>> Ok thats good to hear. Sounds like the Debian package might be dodgy, or
>> they just happened to snapshot at a bad time.
>
> I wonder which version it is - the "debian package".  Are we talking
> about kvm-72 from debian lenny perhaps?
>
> Current version is 0.12.4-1, which is upstream 0.12.4-1 with a few
> bugfixes (such as >1Tb block device corruption).  I'm not sure how
> that one might be "dogdy" or snapshotted at a bad time.
>
> Thanks!
>
> /mjt
>
I am sorry. I made a mistake while testing it. There is no problem
with the Debian package. I get better latency results when i disable
the TX timeout in the virtio-net.c in qemu-kvm. But there is no
improvement over this result when i use vhost.

Thanks,
Bala