Hi all, now we noticed this commit has already merged into mainline, and in our tests there is still similar regression. [1] not sure if there is a plan to merge some of the solutions that have been discussed in this thread? we'll very glad to test patches if there is a request Thanks a lot! [1] ========================================================================================= tbox_group/testcase/rootfs/kconfig/compiler/ip/runtime/nr_threads/cluster/send_size/test/cpufreq_governor/ucode: lkp-icl-2sp4/netperf/debian-11.1-x86_64-20220510.cgz/x86_64-rhel-8.3/gcc-11/ipv4/300s/50%/cs-localhost/10K/SCTP_STREAM_MANY/performance/0xd000363 7c80b038d23e1f4c 4890b686f4088c90432149bd6de ---------------- --------------------------- %stddev %change %stddev \ | \ 9078 -55.9% 4006 netperf.Throughput_Mbps 581006 -55.9% 256385 netperf.Throughput_total_Mbps 36715 -54.6% 16674 ± 4% netperf.time.involuntary_context_switches 1885 -50.2% 938.33 ± 3% netperf.time.percent_of_cpu_this_job_got 5533 -49.9% 2771 ± 2% netperf.time.system_time 152.13 -59.5% 61.61 ± 2% netperf.time.user_time 418171 ± 5% +89.4% 791954 ± 17% netperf.time.voluntary_context_switches 2.128e+09 -55.9% 9.389e+08 netperf.workload 30217 +17.8% 35608 uptime.idle 2.689e+10 +20.3% 3.234e+10 cpuidle..time 6.366e+08 -48.1% 3.305e+08 cpuidle..usage 70.26 +13.5 83.78 mpstat.cpu.all.idle% 4.46 -1.5 2.92 ± 3% mpstat.cpu.all.soft% 23.71 -11.6 12.16 ± 3% mpstat.cpu.all.sys% 0.89 -0.5 0.38 mpstat.cpu.all.usr% 1.392e+09 -57.5% 5.91e+08 ± 12% numa-numastat.node0.local_node 1.389e+09 -57.5% 5.906e+08 ± 12% numa-numastat.node0.numa_hit 1.369e+09 -54.5% 6.226e+08 ± 12% numa-numastat.node1.local_node 1.366e+09 -54.4% 6.222e+08 ± 12% numa-numastat.node1.numa_hit 36715 -54.6% 16674 ± 4% time.involuntary_context_switches 1885 -50.2% 938.33 ± 3% time.percent_of_cpu_this_job_got 5533 -49.9% 2771 ± 2% time.system_time 152.13 -59.5% 61.61 ± 2% time.user_time 418171 ± 5% +89.4% 791954 ± 17% time.voluntary_context_switches On Tue, Jul 05, 2022 at 01:03:26PM +0800, Feng Tang wrote: > On Sun, Jul 03, 2022 at 03:55:31PM -0700, Roman Gushchin wrote: > > On Sun, Jul 03, 2022 at 06:43:53PM +0800, Feng Tang wrote: > > > Hi Shakeel, > > > > > > On Fri, Jul 01, 2022 at 08:47:29AM -0700, Shakeel Butt wrote: > > > > On Mon, Jun 27, 2022 at 8:49 PM Feng Tang <feng.tang@xxxxxxxxx> wrote: > > > > > I just tested it, it does perform better (the 4th is with your patch), > > > > > some perf-profile data is also listed. > > > > > > > > > > 7c80b038d23e1f4c 4890b686f4088c90432149bd6de 332b589c49656a45881bca4ecc0 e719635902654380b23ffce908d > > > > > ---------------- --------------------------- --------------------------- --------------------------- > > > > > 15722 -69.5% 4792 -40.8% 9300 -27.9% 11341 netperf.Throughput_Mbps > > > > > > > > > > 0.00 +0.3 0.26 ± 5% +0.5 0.51 +1.3 1.27 ± 2%pp.self.__sk_mem_raise_allocated > > > > > 0.00 +0.3 0.32 ± 15% +1.7 1.74 ± 2% +0.4 0.40 ± 2% pp.self.propagate_protected_usage > > > > > 0.00 +0.8 0.82 ± 7% +0.9 0.90 +0.8 0.84 pp.self.__mod_memcg_state > > > > > 0.00 +1.2 1.24 ± 4% +1.0 1.01 +1.4 1.44 pp.self.try_charge_memcg > > > > > 0.00 +2.1 2.06 +2.1 2.13 +2.1 2.11 pp.self.page_counter_uncharge > > > > > 0.00 +2.1 2.14 ± 4% +2.7 2.71 +2.6 2.60 ± 2% pp.self.page_counter_try_charge > > > > > 1.12 ± 4% +3.1 4.24 +1.1 2.22 +1.4 2.51 pp.self.native_queued_spin_lock_slowpath > > > > > 0.28 ± 9% +3.8 4.06 ± 4% +0.2 0.48 +0.4 0.68 pp.self.sctp_eat_data > > > > > 0.00 +8.2 8.23 +0.8 0.83 +1.3 1.26 pp.self.__sk_mem_reduce_allocated > > > > > > > > > > And the size of 'mem_cgroup' is increased from 4224 Bytes to 4608. > > > > > > > > Hi Feng, can you please try two more configurations? Take Eric's patch > > > > of adding ____cacheline_aligned_in_smp in page_counter and for first > > > > increase MEMCG_CHARGE_BATCH to 64 and for second increase it to 128. > > > > Basically batch increases combined with Eric's patch. > > > > > > With increasing batch to 128, the regression could be reduced to -12.4%. > > > > If we're going to bump it, I wonder if we should scale it dynamically depending > > on the size of the memory cgroup? > > I think it makes sense, or also make it a configurable parameter? From > the test reports of 0Day, these charging/counting play critical role > in performance (easy to see up to 60% performance effect). If user only > wants memcg for isolating things or doesn't care charging/stats, these > seem to be extra taxes. > > For bumping to 64 or 128, universal improvement is expected with the > only concern of accuracy. > > Thanks, > Feng > > > Thanks!