[linus:master] [vfs] bf630c4016: stress-ng.bind-mount.ops_per_sec 4.4% improvement

[linus:master] [vfs] bf630c4016: stress-ng.bind-mount.ops_per_sec 4.4% improvement

[kernel test robot]

Hello,

kernel test robot noticed a 4.4% improvement of stress-ng.bind-mount.ops_per_sec on:


commit: bf630c40164162ba1d3933c2f5e3397d083e0948 ("vfs: add notifications for mount attach and detach")
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master


testcase: stress-ng
config: x86_64-rhel-9.4
compiler: gcc-12
test machine: 64 threads 2 sockets Intel(R) Xeon(R) Gold 6346 CPU @ 3.10GHz (Ice Lake) with 256G memory
parameters:

	nr_threads: 100%
	disk: 1HDD
	testtime: 60s
	fs: ext4
	test: bind-mount
	cpufreq_governor: performance






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


The kernel config and materials to reproduce are available at:
https://download.01.org/0day-ci/archive/20250421/202504211504.5f3ebfe2-lkp@intel.com

=========================================================================================
compiler/cpufreq_governor/disk/fs/kconfig/nr_threads/rootfs/tbox_group/test/testcase/testtime:
  gcc-12/performance/1HDD/ext4/x86_64-rhel-9.4/100%/debian-12-x86_64-20240206.cgz/lkp-icl-2sp8/bind-mount/stress-ng/60s

commit: 
  0f46d81f2b ("fanotify: notify on mount attach and detach")
  bf630c4016 ("vfs: add notifications for mount attach and detach")

0f46d81f2bce970b bf630c40164162ba1d3933c2f5e 
---------------- --------------------------- 
         %stddev     %change         %stddev
             \          |                \  
    239.00 ±  5%     +12.6%     269.13 ±  6%  perf-sched.wait_and_delay.count.__cond_resched.smpboot_thread_fn.kthread.ret_from_fork.ret_from_fork_asm
    164599            +4.7%     172303        vmstat.system.cs
    191335            +2.9%     196836        vmstat.system.in
     93378            +3.7%      96874        proc-vmstat.nr_shmem
    553581            +2.2%     565891        proc-vmstat.numa_hit
    486549            +2.5%     498853        proc-vmstat.numa_local
      3679            -3.5%       3549        stress-ng.bind-mount.microsecs_per_mount
      1977            -5.8%       1863        stress-ng.bind-mount.microsecs_per_umount
    672707            +4.4%     702611        stress-ng.bind-mount.ops
     11210            +4.4%      11709        stress-ng.bind-mount.ops_per_sec
    393.73            -1.9%     386.40        stress-ng.time.percent_of_cpu_this_job_got
   1717204            +5.0%    1803755        stress-ng.time.voluntary_context_switches
  2.26e+09            +2.4%  2.315e+09        perf-stat.i.branch-instructions
  20796668            +2.3%   21274158        perf-stat.i.branch-misses
    170642            +5.0%     179197        perf-stat.i.context-switches
      2.14            -2.1%       2.10        perf-stat.i.cpi
 1.097e+10            +2.3%  1.122e+10        perf-stat.i.instructions
      2.66            +5.0%       2.80        perf-stat.i.metric.K/sec
      2.10            -2.1%       2.06        perf-stat.overall.cpi
      0.48            +2.1%       0.49        perf-stat.overall.ipc
 2.223e+09            +2.4%  2.277e+09        perf-stat.ps.branch-instructions
  20458454            +2.3%   20926770        perf-stat.ps.branch-misses
    167851            +5.0%     176265        perf-stat.ps.context-switches
 1.079e+10            +2.3%  1.104e+10        perf-stat.ps.instructions
 6.615e+11            +2.4%  6.771e+11        perf-stat.total.instructions




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