Hello,
kernel test robot noticed a 99.9% improvement of dbench.max_latency on:
commit: eccbbc7c00a5aae5e704d4002adfaf4c3fa4b30d ("nfsd: don't use sv_nrthreads in connection limiting calculations.")
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master
testcase: dbench
config: x86_64-rhel-9.4
compiler: gcc-12
test machine: 224 threads 4 sockets Intel(R) Xeon(R) Platinum 8380H CPU @ 2.90GHz (Cooper Lake) with 192G memory
parameters:
nr_threads: 100%
cpufreq_governor: performance
disk: 1HDD
fs: btrfs
fs2: nfs
Details are as below:
-------------------------------------------------------------------------------------------------->
The kernel config and materials to reproduce are available at:
https://download.01.org/0day-ci/archive/20250421/202504211304.eb2ca0c2-lkp@xxxxxxxxx
=========================================================================================
compiler/cpufreq_governor/disk/fs2/fs/kconfig/nr_threads/rootfs/tbox_group/testcase:
gcc-12/performance/1HDD/nfs/btrfs/x86_64-rhel-9.4/100%/debian-12-x86_64-20240206.cgz/lkp-cpl-4sp2/dbench
commit:
de71d4e211 ("nfsd: fix legacy client tracking initialization")
eccbbc7c00 ("nfsd: don't use sv_nrthreads in connection limiting calculations.")
de71d4e211eddb67 eccbbc7c00a5aae5e704d4002ad
---------------- ---------------------------
fail:runs %reproduction fail:runs
| | |
10:10 -100% :10 stderr.has_stderr
10:10 -100% :10 stderr.nfsproc3_create_3_failed_in_nfsio_create
%stddev %change %stddev
\ | \
71006 -99.9% 35.66 ± 7% dbench.max_latency
71006 -99.9% 35.66 ± 7% dbench.max_latency_harmonic_mean
1.11 +0.1 1.16 perf-stat.i.branch-miss-rate%
80903221 +6.3% 86014278 ± 2% perf-stat.i.branch-misses
1.10 +0.1 1.16 perf-stat.overall.branch-miss-rate%
79601951 +6.3% 84615085 ± 2% perf-stat.ps.branch-misses
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
