From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Michael S. Tsirkin" Subject: Re: [PATCHv2 RFC 0/4] virtio and vhost-net capacity handling Date: Mon, 13 Jun 2011 16:35:13 +0300 Message-ID: <20110613133513.GA29884__15487.7606350512$1307973085$gmane$org@redhat.com> References: <20110607160830.GB17581@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org To: Krishna Kumar2 Cc: habanero@linux.vnet.ibm.com, lguest@lists.ozlabs.org, Shirley Ma , kvm@vger.kernel.org, Carsten Otte , linux-s390@vger.kernel.org, Heiko Carstens , linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, steved@us.ibm.com, Christian Borntraeger , Tom Lendacky , netdev@vger.kernel.org, Martin Schwidefsky , linux390@de.ibm.com List-Id: virtualization@lists.linuxfoundation.org On Mon, Jun 13, 2011 at 07:02:27PM +0530, Krishna Kumar2 wrote: > "Michael S. Tsirkin" wrote on 06/07/2011 09:38:30 PM: > > > > This is on top of the patches applied by Rusty. > > > > > > Warning: untested. Posting now to give people chance to > > > comment on the API. > > > > OK, this seems to have survived some testing so far, > > after I dropped patch 4 and fixed build for patch 3 > > (build fixup patch sent in reply to the original). > > > > I'll be mostly offline until Sunday, would appreciate > > testing reports. > > Hi Michael, > > I ran the latest patches with 1K I/O (guest->local host) and > the results are (60 sec run for each test case): Hi! Did you apply this one: [PATCHv2 RFC 4/4] Revert "virtio: make add_buf return capacity remaining" ? It turns out that that patch has a bug and should be reverted, only patches 1-3 should be applied. Could you confirm please? > ___________________/ > #sessions BW% SD% > ______________________________ > 1 -25.6 47.0 > 2 -29.3 22.9 > 4 .8 1.6 > 8 1.6 0 > 16 -1.6 4.1 > 32 -5.3 2.1 > 48 11.3 -7.8 > 64 -2.8 .7 > 96 -6.2 .6 > 128 -10.6 12.7 > ______________________________ > BW: -4.8 SD: 5.4 > > I tested it again to see if the regression is fleeting (since > the numbers vary quite a bit for 1K I/O even between guest-> > local host), but: > > ______________________________ > #sessions BW% SD% > ______________________________ > 1 14.0 -17.3 > 2 19.9 -11.1 > 4 7.9 -15.3 > 8 9.6 -13.1 > 16 1.2 -7.3 > 32 -.6 -13.5 > 48 -28.7 10.0 > 64 -5.7 -.7 > 96 -9.4 -8.1 > 128 -9.4 .7 > ______________________________ > BW: -3.7 SD: -2.0 > > > With 16K, there was an improvement in SD, but > higher sessions seem to slightly degrade BW/SD: > > ______________________________ > #sessions BW% SD% > ______________________________ > 1 30.9 -25.0 > 2 16.5 -19.4 > 4 -1.3 7.9 > 8 1.4 6.2 > 16 3.9 -5.4 > 32 0 4.3 > 48 -.5 .1 > 64 32.1 -1.5 > 96 -2.1 23.2 > 128 -7.4 3.8 > ______________________________ > BW: 5.0 SD: 7.5 > > > Thanks, > > - KK