From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Michael S. Tsirkin" Subject: Re: [v3 RFC PATCH 0/4] Implement multiqueue virtio-net Date: Tue, 26 Oct 2010 13:09:13 +0200 Message-ID: <20101026110913.GC7922@redhat.com> References: <20101020085452.15579.76002.sendpatchset@krkumar2.in.ibm.com> <20101025161718.GA19559@redhat.com> <20101026093846.GA6766@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: anthony@codemonkey.ws, arnd@arndb.de, avi@redhat.com, davem@davemloft.net, eric.dumazet@gmail.com, kvm@vger.kernel.org, netdev@vger.kernel.org, netdev-owner@vger.kernel.org, rusty@rustcorp.com.au To: Krishna Kumar2 Return-path: Content-Disposition: inline In-Reply-To: Sender: kvm-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Tue, Oct 26, 2010 at 03:31:39PM +0530, Krishna Kumar2 wrote: > > "Michael S. Tsirkin" > > > > On Tue, Oct 26, 2010 at 02:38:53PM +0530, Krishna Kumar2 wrote: > > > Results for UDP BW tests (unidirectional, sum across > > > 3 iterations, each iteration of 45 seconds, default > > > netperf, vhosts bound to cpus 0-3; no other tuning): > > > > Is binding vhost threads to CPUs really required? > > What happens if we let the scheduler do its job? > > Nothing drastic, I remember BW% and SD% both improved a > bit as a result of binding. If there's a significant improvement this would mean that we need to rethink the vhost-net interaction with the scheduler. > I started binding vhost thread > after Avi suggested it in response to my v1 patch (he > suggested some more that I haven't done), and have been > doing only this tuning ever since. This is part of his > mail for the tuning: > > > vhost: > > thread #0: CPU0 > > thread #1: CPU1 > > thread #2: CPU2 > > thread #3: CPU3 > > I simply bound each thread to CPU0-3 instead. > > Thanks, > > - KK