From mboxrd@z Thu Jan 1 00:00:00 1970 From: ANNIE LI Subject: Re: [Xen-devel] [PATCH 0/4] Implement persistent grant in xen-netfront/netback Date: Thu, 15 Nov 2012 17:02:10 +0800 Message-ID: <50A4AF92.20206@oracle.com> References: <1352962987-541-1-git-send-email-annie.li@oracle.com> <20121115074057.GO8912@reaktio.net> <50A4AA06.8080900@oracle.com> <1352969519.3499.30.camel@zakaz.uk.xensource.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <1352969519.3499.30.camel@zakaz.uk.xensource.com> Sender: netdev-owner@vger.kernel.org To: Ian Campbell Cc: =?UTF-8?B?UGFzaSBLw6Rya2vDpGluZW4=?= , "xen-devel@lists.xensource.com" , "netdev@vger.kernel.org" , "konrad.wilk@oracle.com" List-Id: xen-devel@lists.xenproject.org On 2012-11-15 16:51, Ian Campbell wrote: > On Thu, 2012-11-15 at 08:38 +0000, ANNIE LI wrote: >> On 2012-11-15 15:40, Pasi K=C3=A4rkk=C3=A4inen wrote: >>> Hello, >>> >>> On Thu, Nov 15, 2012 at 03:03:07PM +0800, Annie Li wrote: >>>> This patch implements persistent grants for xen-netfront/netback. = This >>>> mechanism maintains page pools in netback/netfront, these page poo= ls is used to >>>> save grant pages which are mapped. This way improve performance wh= ich is wasted >>>> when doing grant operations. >>>> >>>> Current netback/netfront does map/unmap grant operations frequentl= y when >>>> transmitting/receiving packets, and grant operations costs much cp= u clock. In >>>> this patch, netfront/netback maps grant pages when needed and then= saves them >>>> into a page pool for future use. All these pages will be unmapped = when >>>> removing/releasing the net device. >>>> >>> Do you have performance numbers available already? with/without per= sistent grants? >> I have some simple netperf/netserver test result with/without persis= tent >> grants, >> >> Following is result of with persistent grant patch, >> Guests, Sum, Avg, Min, Max >> 1, 15106.4, 15106.4, 15106.36, 15106.36 >> 2, 13052.7, 6526.34, 6261.81, 6790.86 >> 3, 12675.1, 6337.53, 6220.24, 6454.83 >> 4, 13194, 6596.98, 6274.70, 6919.25 > Are these pairs of guests or individual ones? They are pairs of guests. > > I think the really interesting cases are when you get up to larger > numbers of guests, aren't they? Right. > ISTR that for blkio things got most > interesting WRT persistent grants at the dozens of guests stage. Do y= ou > have any numbers for those? No, I will run more test with more gusets. > > Have you run any tests other than netperf? No, I didn't. > > Do you have numbers for a a persistent capable backend with a > non-persistent frontend and vice versa? I did it, but the test only runs with 4 guests too=EF=BC=8Cwill test wi= th more=20 guests. Thanks Annie > > >> >> Following are result of without persistent patch >> >> Guests, Sum, Avg, Min, Max >> 1, 10864.1, 10864.1, 10864.10, 10864.10 >> 2, 10898.5, 5449.24, 4862.08, 6036.40 >> 3, 10734.5, 5367.26, 5261.43, 5473.08 >> 4, 10924, 5461.99, 5314.84, 5609.14 >