> -----Original Message----- > From: Ding, Xuan <xuan.d...@intel.com> > Sent: Friday, July 8, 2022 3:04 PM > To: Maxime Coquelin <maxime.coque...@redhat.com>; Xia, Chenbo > <chenbo....@intel.com> > Cc: dev@dpdk.org; Hu, Jiayu <jiayu...@intel.com>; He, Xingguang > <xingguang...@intel.com>; Yang, YvonneX <yvonnex.y...@intel.com>; > Jiang, Cheng1 <cheng1.ji...@intel.com> > Subject: RE: [PATCH] vhost: fix unnecessary dirty page logging > > Hi, > > > -----Original Message----- > > From: Maxime Coquelin <maxime.coque...@redhat.com> > > Sent: 2022年7月7日 19:31 > > To: Xia, Chenbo <chenbo....@intel.com>; Ding, Xuan > > <xuan.d...@intel.com> > > Cc: dev@dpdk.org; Hu, Jiayu <jiayu...@intel.com>; He, Xingguang > > <xingguang...@intel.com>; Yang, YvonneX <yvonnex.y...@intel.com>; > > Jiang, > > Cheng1 <cheng1.ji...@intel.com> > > Subject: Re: [PATCH] vhost: fix unnecessary dirty page logging > > > > > > > > On 7/7/22 11:51, Xia, Chenbo wrote: > > >> -----Original Message----- > > >> From: Ding, Xuan <xuan.d...@intel.com> > > >> Sent: Thursday, July 7, 2022 2:55 PM > > >> To: maxime.coque...@redhat.com; Xia, Chenbo <chenbo....@intel.com> > > >> Cc: dev@dpdk.org; Hu, Jiayu <jiayu...@intel.com>; He, Xingguang > > >> <xingguang...@intel.com>; Yang, YvonneX <yvonnex.y...@intel.com>; > > >> Jiang, > > >> Cheng1 <cheng1.ji...@intel.com>; Ding, Xuan <xuan.d...@intel.com> > > >> Subject: [PATCH] vhost: fix unnecessary dirty page logging > > >> > > >> From: Xuan Ding <xuan.d...@intel.com> > > >> > > >> The dirty page logging is only required in vhost enqueue direction > > >> for live migration. This patch removes the unnecessary dirty page > > >> logging in vhost dequeue direction. Otherwise, it will result in a > > >> performance drop. Some if-else judgements are also optimized to > > >> improve > > performance. > > >> > > >> Fixes: 6d823bb302c7 ("vhost: prepare sync for descriptor to mbuf > > >> refactoring") > > >> Fixes: b6eee3e83402 ("vhost: fix sync dequeue offload") > > >> > > >> Signed-off-by: Xuan Ding <xuan.d...@intel.com> > > >> --- > > > > > > Reviewed-by: Chenbo Xia <chenbo....@intel.com> > > > > > > Although it's late in release, we can consider to merge this as I > > > see it impacts the performance by 5%: > > > > > > http://inbox.dpdk.org/dev/BYAPR11MB2711F13CDA2B0A4535A6591EFE839 > @B > > YAPR > > > 11MB2711.namprd11.prod.outlook.com/T/#t > > > > Yes, I raised we need it in -rc4 at today's Release status meeting. > > I'll review it today. > > > > > But also, it will be good to know the performance issue is solved by > > > sharing the test results. > > > > Yes, Intel performance results would be appreciated. > > This fix patch is for the issue reported at 22.07-rc3. The refactoring patch > brings a 3%~5% perf drop in vhost sync path. > With fix patch, the perf drop introduced by refactoring is solved.
The fix is for a critical issue, I tested dpdk22.07-rc3 with the patch, the performance drop introduced by refactoring have been fixed and no other regressions were seen as a result of the patch, but the packed ring still exist drop around 5%. Tested-by: Xingguang He<xingguang...@intel.com> > > However, the testing result shows there still exists ~5% packed ring perf drop > compared with 22.03. > We find the improving checksum offload patch series in 22.07 may contribute > to the packed ring perf drop. > Because we always do checksum checks in PMD. I tested the performance of Vhost before and after checksum offload patch series, there exist ~5% performance drop. > > Could you help to double check this patch series, is it as expected? > Your assistance is really appreciated. > > Regards, > Xuan > > > > > > Thanks, > > > Chenbo > > > > > > > Thanks, > > Maxime