From mboxrd@z Thu Jan  1 00:00:00 1970
From: Shirley Ma <mashirle@us.ibm.com>
Subject: Re: [RFC PATCH 1/1] vhost: TX used buffer guest signal accumulation
Date: Thu, 28 Oct 2010 08:24:37 -0700
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Cc: David Miller <davem@davemloft.net>, netdev@vger.kernel.org,
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To: "Michael S. Tsirkin" <mst@redhat.com>
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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