Re: [RFC PATCH 1/1] vhost: TX used buffer guest signal accumulation

Shirley Ma
2010-10-28T15:24:37Z

On Thu, 2010-10-28 at 07:20 +0200, Michael S. Tsirkin wrote:
> My concern is this can delay signalling for unlimited time.
> Could you pls test this with guests that do not have
> 2b5bbe3b8bee8b38bdc27dd9c0270829b6eb7eeb
> b0c39dbdc204006ef3558a66716ff09797619778
> that is 2.6.31 and older?

I will test it out.

> This seems to be slighltly out of spec, even though
> for TX, signals are less important.
> Two ideas:
> 1. How about writing out used, just delaying the signal?
> This way we don't have to queue separately.
> 2. How about flushing out queued stuff before we exit
> the handle_tx loop? That would address most of
> the spec issue.

I will modify the patch to test out the performance for both 1 & 2
approaches.

Thanks
Shirley