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

[Peter Lieven]

Dietmar Maurer wrote:
>> Meanwhile I quickly tried to reproduce but didn't succeed so far
>> (>10GBit
>> between host and guest with vhost=on and 2 guest cores).
>> However, I finally realized that we are talking about a pretty special
>> host
>> kernel which I don't have around. I guess this is better dealt with by
>> Red Hat
>> folks. Specifically, they should know what features that kernel exposes
>> and
>> what it lacks.
>
> You can also reproduce the bug with Ubuntu 12.04 on the host - it is not
> red-hat related.

Dietmar, how is the speed if you specify --machine pc,kernel_irqchip=off
as cmdline option to qemu-kvm-1.2.0?

Peter