[linus:master] [cgroup/cpuset] 2125c0034c: stress-ng.cpu-online.ops_per_sec 17.8% improvement

[kernel test robot]

Hello,

kernel test robot noticed a 17.8% improvement of stress-ng.cpu-online.ops_per_sec on:


commit: 2125c0034c5dfd61171b494bd309bb7637bff6eb ("cgroup/cpuset: Make cpuset hotplug processing synchronous")
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master

testcase: stress-ng
test machine: 64 threads 2 sockets Intel(R) Xeon(R) Gold 6346 CPU @ 3.10GHz (Ice Lake) with 256G memory
parameters:

	nr_threads: 100%
	testtime: 60s
	test: cpu-online
	cpufreq_governor: performance


In addition to that, the commit also has significant impact on the following tests:

+------------------+---------------------------------------------------------------------------------------------+
| testcase: change | stress-ng: stress-ng.cpu-online.ops_per_sec 13.1% improvement                               |
| test machine     | 224 threads 2 sockets Intel(R) Xeon(R) Platinum 8480CTDX (Sapphire Rapids) with 512G memory |
| test parameters  | cpufreq_governor=performance                                                                |
|                  | nr_threads=100%                                                                             |
|                  | test=cpu-online                                                                             |
|                  | testtime=60s                                                                                |
+------------------+---------------------------------------------------------------------------------------------+




Details are as below:
-------------------------------------------------------------------------------------------------->


The kernel config and materials to reproduce are available at:
https://download.01.org/0day-ci/archive/20240522/202405222215.d537a85f-oliver.sang@xxxxxxxxx

=========================================================================================
compiler/cpufreq_governor/kconfig/nr_threads/rootfs/tbox_group/test/testcase/testtime:
  gcc-13/performance/x86_64-rhel-8.3/100%/debian-12-x86_64-20240206.cgz/lkp-icl-2sp9/cpu-online/stress-ng/60s

commit: 
  4793cb599b ("selftests: cgroup: skip test_cgcore_lesser_ns_open when cgroup2 mounted without nsdelegate")
  2125c0034c ("cgroup/cpuset: Make cpuset hotplug processing synchronous")

4793cb599b1bdc3d 2125c0034c5dfd61171b494bd30 
---------------- --------------------------- 
         %stddev     %change         %stddev
             \          |                \  
 2.751e+09 ±  2%      -9.7%  2.483e+09 ±  2%  cpuidle..time
      4.07 ± 12%     -20.6%       3.23 ± 11%  vmstat.procs.r
      2.87            +0.5        3.34 ±  4%  mpstat.cpu.all.sys%
     16.83 ± 37%     -68.3%       5.33 ± 64%  mpstat.max_utilization.seconds
      1130 ± 23%     +72.3%       1948 ± 14%  numa-meminfo.node0.Active
      1119 ± 24%     +69.2%       1894 ± 15%  numa-meminfo.node0.Active(anon)
    280.28 ± 24%     +69.1%     474.04 ± 15%  numa-vmstat.node0.nr_active_anon
    280.28 ± 24%     +69.1%     474.03 ± 15%  numa-vmstat.node0.nr_zone_active_anon
      0.03 ± 63%    +202.3%       0.10 ± 65%  perf-stat.i.major-faults
      0.03 ± 62%    +200.9%       0.09 ± 65%  perf-stat.ps.major-faults
    171.45 ± 14%     -25.8%     127.20 ± 17%  sched_debug.cfs_rq:/.load_avg.avg
    116.43 ± 10%     -31.4%      79.84 ± 23%  sched_debug.cfs_rq:/.removed.load_avg.avg
    319.20 ±  4%     -16.3%     267.32 ± 10%  sched_debug.cfs_rq:/.removed.load_avg.stddev
    111.20 ± 45%    +114.3%     238.25 ± 32%  stress-ng.cpu-online.millisecs_per_online_action
    516.50           +14.8%     593.00 ±  3%  stress-ng.cpu-online.ops
      7.72 ±  2%     +17.8%       9.09 ±  3%  stress-ng.cpu-online.ops_per_sec


***************************************************************************************************
lkp-spr-2sp4: 224 threads 2 sockets Intel(R) Xeon(R) Platinum 8480CTDX (Sapphire Rapids) with 512G memory
=========================================================================================
compiler/cpufreq_governor/kconfig/nr_threads/rootfs/tbox_group/test/testcase/testtime:
  gcc-13/performance/x86_64-rhel-8.3/100%/debian-12-x86_64-20240206.cgz/lkp-spr-2sp4/cpu-online/stress-ng/60s

commit: 
  4793cb599b ("selftests: cgroup: skip test_cgcore_lesser_ns_open when cgroup2 mounted without nsdelegate")
  2125c0034c ("cgroup/cpuset: Make cpuset hotplug processing synchronous")

4793cb599b1bdc3d 2125c0034c5dfd61171b494bd30 
---------------- --------------------------- 
         %stddev     %change         %stddev
             \          |                \  
    -13.50           +34.6%     -18.17        sched_debug.cpu.nr_uninterruptible.min
     59969            +5.2%      63066        vmstat.system.cs
      0.54 ±  4%      +0.1        0.63 ±  2%  mpstat.cpu.all.irq%
      0.17 ±  3%      +0.0        0.18 ±  2%  mpstat.cpu.all.usr%
      1678 ±  5%     +13.9%       1912 ±  7%  perf-stat.i.cpu-migrations
      1660 ±  5%     +13.9%       1890 ±  7%  perf-stat.ps.cpu-migrations
    479.33 ±  4%      +7.5%     515.50        stress-ng.cpu-online.ops
      4.86 ±  4%     +13.1%       5.50 ±  3%  stress-ng.cpu-online.ops_per_sec



Disclaimer:
Results have been estimated based on internal Intel analysis and are provided
for informational purposes only. Any difference in system hardware or software
design or configuration may affect actual performance.


-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki