[linus:master] [sched] 89951fc1f8: stress-ng.enosys.ops_per_sec 4.7% improvement

From: kernel test robot

Date: Thu Feb 26 2026 - 02:49:36 EST




Hello,

kernel test robot noticed a 4.7% improvement of stress-ng.enosys.ops_per_sec on:


commit: 89951fc1f8201df27366ac1eed1ddc9ee0f47729 ("sched: Reorder some fields in struct rq")
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master


testcase: stress-ng
config: x86_64-rhel-9.4
compiler: gcc-14
test machine: 256 threads 4 sockets INTEL(R) XEON(R) PLATINUM 8592+ (Emerald Rapids) with 256G memory
parameters:

nr_threads: 100%
testtime: 60s
test: enosys
cpufreq_governor: performance



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


The kernel config and materials to reproduce are available at:
https://download.01.org/0day-ci/archive/20260226/202602261519.645f013d-lkp@xxxxxxxxx

=========================================================================================
compiler/cpufreq_governor/kconfig/nr_threads/rootfs/tbox_group/test/testcase/testtime:
gcc-14/performance/x86_64-rhel-9.4/100%/debian-13-x86_64-20250902.cgz/lkp-emr-2sp1/enosys/stress-ng/60s

commit:
55b39b0cf1 ("sched/fair: Use cpumask_weight_and() in sched_balance_find_dst_group()")
89951fc1f8 ("sched: Reorder some fields in struct rq")

55b39b0cf183b9c6 89951fc1f8201df27366ac1eed1
---------------- ---------------------------
%stddev %change %stddev
\ | \
8.757e+08 +4.7% 9.169e+08 stress-ng.enosys.ops
14602390 +4.7% 15290136 stress-ng.enosys.ops_per_sec
114078 +4.7% 119451 stress-ng.enosys.syscalls_per_second
3314145 +4.6% 3466972 stress-ng.time.minor_page_faults
8699 -1.4% 8575 stress-ng.time.system_time
1649 +4.8% 1728 stress-ng.time.user_time
1.661e+09 +5.0% 1.744e+09 stress-ng.time.voluntary_context_switches
9.917e+08 +6.4% 1.055e+09 cpuidle..usage
44556222 +3.9% 46298755 vmstat.system.cs
1.05 -0.0 1.00 turbostat.C1E%
0.56 +4.7% 0.58 turbostat.IPC
2.20 +0.4 2.56 ± 2% turbostat.POLL%
7.024e+10 +4.2% 7.32e+10 perf-stat.i.branch-instructions
5.411e+08 +3.7% 5.613e+08 perf-stat.i.branch-misses
27.00 +3.6 30.63 perf-stat.i.cache-miss-rate%
1.393e+09 +4.5% 1.456e+09 perf-stat.i.cache-misses
5.185e+09 -8.1% 4.764e+09 perf-stat.i.cache-references
46807212 +4.5% 48921785 perf-stat.i.context-switches
1.92 -4.3% 1.83 perf-stat.i.cpi
12283691 +5.4% 12944082 perf-stat.i.cpu-migrations
466.69 -4.3% 446.75 perf-stat.i.cycles-between-cache-misses
3.489e+11 +4.3% 3.639e+11 perf-stat.i.instructions
0.54 +4.2% 0.57 perf-stat.i.ipc
230.75 +4.7% 241.60 perf-stat.i.metric.K/sec
26.88 +3.7 30.56 perf-stat.overall.cache-miss-rate%
1.85 -4.2% 1.77 perf-stat.overall.cpi
462.88 -4.3% 442.84 perf-stat.overall.cycles-between-cache-misses
0.54 +4.3% 0.56 perf-stat.overall.ipc
6.91e+10 +4.2% 7.201e+10 perf-stat.ps.branch-instructions
5.32e+08 +3.7% 5.518e+08 perf-stat.ps.branch-misses
1.37e+09 +4.5% 1.431e+09 perf-stat.ps.cache-misses
5.098e+09 -8.1% 4.684e+09 perf-stat.ps.cache-references
46015345 +4.5% 48090269 perf-stat.ps.context-switches
12075501 +5.4% 12723669 perf-stat.ps.cpu-migrations
3.432e+11 +4.3% 3.579e+11 perf-stat.ps.instructions
2.085e+13 +4.7% 2.183e+13 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