Hi Eric, Just FYI, we noticed the below changes in old commit 878d7439d0 ("rcu: Fix batch-limit size problem") in test case will-it-scale/open1:
62da1921292ef78 878d7439d0f45a95869e41757 --------------- ------------------------- 0.00 ~200% +60900.0% 1.22 ~18% TOTAL perf-profile.cpu-clock.file_free_rcu.rcu_process_callbacks.__do_softirq.call_softirq.do_softirq 0.28 ~126% +339.3% 1.23 TOTAL perf-profile.cpu-clock.__d_lookup_rcu.link_path_walk.do_filp_open.do_sys_open.sys_open 1.16 ~15% -100.0% 0.00 TOTAL perf-profile.cpu-clock.file_free_rcu.rcu_process_callbacks.__do_softirq.run_ksoftirqd.smpboot_thread_fn 1.89e+08 ~14% -100.0% 63093 ~ 6% TOTAL softirqs.RCU 3.66 ~ 7% -100.0% 0.00 TOTAL perf-profile.cpu-clock.rcu_process_callbacks.__do_softirq.run_ksoftirqd.smpboot_thread_fn.kthread 1.29 ~11% -100.0% 0.00 TOTAL perf-profile.cpu-clock.rcu_process_gp_end.isra.23.rcu_process_callbacks.__do_softirq.run_ksoftirqd.smpboot_thread_fn 1.39 ~ 9% -100.0% 0.00 TOTAL perf-profile.cpu-clock.check_for_new_grace_period.isra.25.rcu_process_callbacks.__do_softirq.run_ksoftirqd.smpboot_thread_fn 57276 ~ 9% +110.2% 120367 ~15% TOTAL slabinfo.kmalloc-256.active_objs 3582 ~ 9% +110.0% 7525 ~15% TOTAL slabinfo.kmalloc-256.active_slabs 3582 ~ 9% +110.0% 7525 ~15% TOTAL slabinfo.kmalloc-256.num_slabs 57331 ~ 9% +110.0% 120407 ~15% TOTAL slabinfo.kmalloc-256.num_objs 23741 ~ 6% +71.2% 40652 ~13% TOTAL meminfo.SUnreclaim 19830 ~ 4% -44.1% 11094 ~ 8% TOTAL interrupts.RES 6113 ~ 8% +74.6% 10674 ~12% TOTAL proc-vmstat.nr_slab_unreclaimable 2.44 ~13% +62.9% 3.98 ~13% TOTAL perf-profile.cpu-clock.__slab_alloc.kmem_cache_alloc.get_empty_filp.do_filp_open.do_sys_open 3 ~ 0% -33.3% 2 ~ 0% TOTAL vmstat.procs.r 53183 ~ 3% +31.6% 70006 ~ 8% TOTAL meminfo.Slab 1001 ~ 9% -14.3% 858 ~10% TOTAL slabinfo.kmalloc-128.num_objs 1001 ~ 9% -14.3% 858 ~10% TOTAL slabinfo.kmalloc-128.active_objs 2.47 ~ 7% +12.1% 2.76 ~ 6% TOTAL perf-profile.cpu-clock.__call_rcu.call_rcu_sched.__fput.____fput.task_work_run 6686 ~ 5% -95.9% 272 ~ 3% TOTAL time.involuntary_context_switches 109 ~ 1% +21.3% 132 ~ 1% TOTAL time.system_time 55 ~ 0% +19.6% 66 ~ 0% TOTAL time.percent_of_cpu_this_job_got 899 ~ 3% +10.5% 993 ~ 7% TOTAL vmstat.system.cs time.system_time 140 ++-------------------------------------------------------------------+ | O O O O | 135 ++ | O O O O O O O O O O O O O O O O O O O O O 130 ++ O O O O O O O O O | | | 125 ++ | | | 120 ++ | | | 115 ++ | | .*. .*. *.. | 110 *+ .*. .*. .*.*.*. .* *.*.*..*.*.*.* *. .*. + .*. | | * *.*.*. * * * *.* *.* * | 105 ++-------------------------------------------------------------------+ time.percent_of_cpu_this_job_got 66 O+O-O-O-O--O-O-O-O-O-O-O-O--O-O-O-O-O-O-O-O--O-O-O-O-O-O-O-O--O-O-O-O-O | | 64 ++ | | | | | 62 ++ | | | 60 ++ | | | 58 ++ | | * * | | + + + + | 56 ++ .*.*. + *.*.*.*.* *..*.*. .*. | *.*.*.*.*..*.*.*.* *.* *.*.*.* *..*.*.* | 54 ++--------------------------------------------------------------------+ time.involuntary_context_switches 9000 ++------------------------------------------------------------------+ | * | 8000 ++ .*.*. .* * *. .*.*. .* *. + + .*. | 7000 *+* * + + + .. * *.*.*.*.* + + *.* *. *. .*.*. | | * * * * *.* | 6000 ++ | 5000 ++ | | | 4000 ++ | 3000 ++ | | | 2000 ++ | 1000 ++ | | O O O | 0 O+--O-O---O---O-O--O-O-O-O-O-O-O-O-O-O-O-O-O-O-O-O--O-O-O-O-O-O-O-O-O -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/