From mboxrd@z Thu Jan  1 00:00:00 1970
From: Shirley Ma <mashirle@us.ibm.com>
Subject: Re: [PATCH 1/2] vhost: allow multiple workers threads
Date: Mon, 20 Feb 2012 17:04:10 -0800
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Cc: Anthony Liguori <aliguori@us.ibm.com>,
	Tom Lendacky <toml@us.ibm.com>, netdev@vger.kernel.org,
	Cristian Viana <vianac@br.ibm.com>
To: "Michael S. Tsirkin" <mst@redhat.com>
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On Mon, 2012-02-20 at 23:00 +0200, Michael S. Tsirkin wrote:
> 
> The point was really to avoid scheduler overhead
> as with tcp, tx and rx tend to run on the same cpu.

We have tried different approaches in the past, like splitting vhost
thread to separate TX, RX threads; create per cpu vhost thread instead
of creating per VM per virtio_net vhost thread... 

We think per cpu vhost thread is a better approach based on the data we
have collected. It will reduce both vhost resource and scheduler
overhead. It will not depend on host scheduler, has less various. The
patch is under testing, we hope we can post it soon.

Thanks
Shirley