On Mon, Aug 22, 2022 at 12:55 AM Shakeel Butt <shakeelb@xxxxxxxxxx> wrote: > > On Sun, Aug 21, 2022 at 5:24 PM Soheil Hassas Yeganeh <soheil@xxxxxxxxxx> wrote: > > > > On Sun, Aug 21, 2022 at 8:18 PM Shakeel Butt <shakeelb@xxxxxxxxxx> wrote: > > > > > > With memcg v2 enabled, memcg->memory.usage is a very hot member for > > > the workloads doing memcg charging on multiple CPUs concurrently. > > > Particularly the network intensive workloads. In addition, there is a > > > false cache sharing between memory.usage and memory.high on the charge > > > path. This patch moves the usage into a separate cacheline and move all > > > the read most fields into separate cacheline. > > > > > > To evaluate the impact of this optimization, on a 72 CPUs machine, we > > > ran the following workload in a three level of cgroup hierarchy with top > > > level having min and low setup appropriately. More specifically > > > memory.min equal to size of netperf binary and memory.low double of > > > that. > > > > > > $ netserver -6 > > > # 36 instances of netperf with following params > > > $ netperf -6 -H ::1 -l 60 -t TCP_SENDFILE -- -m 10K > > > > > > Results (average throughput of netperf): > > > Without (6.0-rc1) 10482.7 Mbps > > > With patch 12413.7 Mbps (18.4% improvement) > > > > > > With the patch, the throughput improved by 18.4%. > > > > Shakeel, for my understanding: is this on top of the gains from the > > previous patch? > > > > No, this is independent of the previous patch. The cover letter has > the numbers for all three optimizations applied together. Acked-by: Soheil Hassas Yeganeh <soheil@xxxxxxxxxx>
