[Qemu-devel] is there a way to optimize vhost of virtio-net

[Qemu-devel] is there a way to optimize vhost of virtio-net

[yue]

hi, jasowang:
     according to my test , the vm's network performance is just 20% of physical ethernet, the thread of vhost  easily eat up 100% cpu when under pressure.
when using multi queue(two queues) the performance goes up by 50%, but it uses more threads.
if we can come to a conclusion that vhost is bottomneck?  or do you have any idea to improve , first we do not need to care how  violent  the idea   is.




thanks

Re: [Qemu-devel] is there a way to optimize vhost of virtio-net

[Jason Wang]

On 2016年10月17日 18:39, yue wrote:
> hi, jasowang:
>       according to my test , the vm's network performance is just 20% of physical ethernet, the thread of vhost  easily eat up 100% cpu when under pressure.

What's you configuration (e.g qemu cli, host and guest kernel versions 
and network setups). And how do you measure the performance?

> when using multi queue(two queues) the performance goes up by 50%, but it uses more threads.
> if we can come to a conclusion that vhost is bottomneck?  or do you have any idea to improve , first we do not need to care how  violent  the idea   is.

We notice the small packet TCP stream performance was bad in the past, 
but not sure it was your case.

>
>
>
> thanks

[Qemu-devel] is there a way to optimize vhost of virtio-net

[yue]

hi, jasowang:
     according to my test , the vm's network performance is just 20% of physical ethernet, the thread of vhost  easily eat up 100% cpu when under pressure.
when using multi queue(two queues) the performance goes up by 50%, but it uses more threads.
if we can come to a conclusion that vhost is bottomneck?  or do you have any idea to improve , first we do not need to care how  violent  the idea   is.




thanks




 

[Qemu-devel] is there a way to optimize vhost of virtio-net

[yue]

hi, jasowang:
     according to my test , the vm's network performance is just 20% of physical ethernet, the thread of vhost  easily eat up 100% cpu when under pressure.
when using multi queue(two queues) the performance goes up by 50%, but it uses more threads.
if we can come to a conclusion that vhost is bottomneck?  or do you have any idea to improve , first we do not need to care how  violent  the idea   is.




thanks