Re: [Qemu-devel] slow virtio network with vhost=on and multiple cores

[Alexandre DERUMIER]

>>Have you had any further progress on this regression/problem?

Hi Peter,
I didn't re-tested myself,
but a proxmox user who's have the problem with qemu-kvm 1.2, with windows guest 
and linux guest,
don't have the problem anymore with qemu 1.3.

http://forum.proxmox.com/threads/12157-Win2003R2-in-KVM-VM-is-slow-in-PVE-2-2-when-multiply-CPU-cores-allowed

I'll try to redone test myself this week

Regards,

Alexandre

----- Mail original -----

De: "Peter Lieven" <address@hidden>
À: "Alexandre DERUMIER" <address@hidden>
Cc: "Dietmar Maurer" <address@hidden>, "Stefan Hajnoczi" <address@hidden>, "Jan 
Kiszka" <address@hidden>, address@hidden, "Michael S. Tsirkin" 
<address@hidden>, "Peter Lieven" <address@hidden>
Envoyé: Lundi 3 Décembre 2012 12:23:11
Objet: Re: [Qemu-devel] slow virtio network with vhost=on and multiple cores


Am 16.11.2012 um 12:00 schrieb Alexandre DERUMIER <address@hidden>:

>>> While trying to reproduce the bug, we just detected that it depends on the 
>>> hardware (mainboard) you run on.
>>>
>>> Sigh :-/
>
> Hi,
>
> I can reproduce the bug on all my dell servers,differents generation (R710 
> (intel),R815 (amd), 2950 (intel).
>
> They all use broadcom bnx2 network card (don't know if it can be related)
>
> host kernel : rhel 63 with 2.6.32 kernel
>
> guest kernel : 2.6.32 (debian squeeze, ubuntu).
>
> No problem with guest kernel 3.2

Have you had any further progress on this regression/problem?

Thanks,
Peter

>
>
>
>
> ----- Mail original -----
>
> De: "Dietmar Maurer" <address@hidden>
> À: "Peter Lieven" <address@hidden>
> Cc: "Stefan Hajnoczi" <address@hidden>, "Peter Lieven" <address@hidden>, "Jan 
> Kiszka" <address@hidden>, address@hidden, "Michael S. Tsirkin" 
> <address@hidden>
> Envoyé: Vendredi 16 Novembre 2012 11:44:26
> Objet: Re: [Qemu-devel] slow virtio network with vhost=on and multiple cores
>
>>> I only tested with RHEL6.3 kernel on host.
>>
>> can you check if there is a difference on interrupt delivery between those
>> two?
>>
>> cat /proc/interrupts should be sufficient after some traffic has flown. 
>
> While trying to reproduce the bug, we just detected that it depends on the 
> hardware (mainboard) you run on.
>
> Sigh :-/