Re: [Qemu-devel] Re: [PATCH 2/3] virtio-pci: Use ioeventfd for virtqueue notify

Stefan Hajnoczi
2010-11-15T11:20:20Z

On Sun, Nov 14, 2010 at 12:19 PM, Avi Kivity <avi@redhat.com> wrote:
> On 11/14/2010 01:05 PM, Avi Kivity wrote:
>>>
>>> I agree, but let's enable virtio-ioeventfd carefully because bad code
>>> is out there.
>>
>>
>> Sure.  Note as long as the thread waiting on ioeventfd doesn't consume too
>> much cpu, it will awaken quickly and we won't have the "transaction per
>> timeslice" effect.
>>
>> btw, what about virtio-blk with linux-aio?  Have you benchmarked that with
>> and without ioeventfd?
>>
>
> And, what about efficiency?  As in bits/cycle?

We are running benchmarks with this latest patch and will report results.

Stefan