Greeting, FYI, we noticed a -18.8% regression of will-it-scale.per_process_ops due to commit: commit: 2be1f41c14fa1921cf2217483f48a0b9b423be37 ("x86/entry/64: Create a percpu SYSCALL entry trampoline") https://git.kernel.org/cgit/linux/kernel/git/luto/linux.git x86/entry_stack in testcase: will-it-scale on test machine: 32 threads Intel(R) Xeon(R) CPU E5-2680 0 @ 2.70GHz with 64G memory with following parameters: test: lseek2 cpufreq_governor: performance test-description: Will It Scale takes a testcase and runs it from 1 through to n parallel copies to see if the testcase will scale. It builds both a process and threads based test in order to see any differences between the two. test-url: https://github.com/antonblanchard/will-it-scale In addition to that, the commit also has significant impact on the following tests: +------------------+------------------------------------------------------------------+ | testcase: change | vm-scalability: vm-scalability.median -1.1% improvement | | test machine | 4 threads Intel(R) Core(TM) i5-2300 CPU @ 2.80GHz with 4G memory | | test parameters | cpufreq_governor=performance | | | runtime=300s | | | test=lru-file-readtwice | +------------------+------------------------------------------------------------------+ Details are as below: --------------------------------------------------------------------------------------------------> To reproduce: git clone https://github.com/intel/lkp-tests.git cd lkp-tests bin/lkp install job.yaml # job file is attached in this email bin/lkp run job.yaml testcase/path_params/tbox_group/run: will-it-scale/lseek2-performance/lkp-sb03 9f2327b9ef846266 2be1f41c14fa1921cf2217483f ---------------- -------------------------- 470 17% 551 will-it-scale.time.user_time 0.64 8% 0.69 will-it-scale.scalability 2039 -4% 1958 will-it-scale.time.system_time 9781767 -13% 8489674 will-it-scale.per_thread_ops 16296316 -19% 13231829 will-it-scale.per_process_ops fail:runs %reproduction fail:runs | | | :4 25% 1:4 dmesg.RIP:load_balance :4 50% 2:4 dmesg.RIP:__fget :4 25% 1:4 dmesg.RIP:native_sched_clock :4 25% 1:4 dmesg.RIP:__update_idle_core :4 25% 1:4 dmesg.RIP:rcu_all_qs :4 25% 1:4 dmesg.RIP:__update_load_avg_se :4 25% 1:4 dmesg.RIP:delay_tsc :4 25% 1:4 dmesg.RIP:prepare_to_wait :4 25% 1:4 dmesg.RIP:trigger_load_balance 4:4 -100% :4 dmesg.RIP:entry_SYSCALL_64 1:4 -25% :4 dmesg.RIP:__switch_to 1:4 -25% :4 dmesg.RIP:ktime_get_update_offsets_now 1:4 -25% :4 dmesg.RIP:update_curr 1:4 -25% :4 dmesg.RIP:_raw_spin_lock 1:4 -25% :4 dmesg.RIP:__tick_nohz_idle_enter 1:4 -25% :4 dmesg.RIP:native_write_msr 0.01 48965% 3.82 perf-stat.branch-miss-rate% 2.349e+08 42829% 1.009e+11 perf-stat.branch-misses 1.128e+08 ± 17% 41% 1.588e+08 ± 16% perf-stat.iTLB-loads 1.20 17% 1.39 perf-stat.cpi 0.00 ± 9% 15% 0.00 perf-stat.dTLB-store-miss-rate% 2.688e+12 ± 3% -12% 2.353e+12 perf-stat.dTLB-stores 3.02e+12 -13% 2.642e+12 perf-stat.branch-instructions 0.84 -14% 0.72 perf-stat.ipc 1.351e+13 -14% 1.156e+13 perf-stat.instructions 4.395e+12 -15% 3.754e+12 perf-stat.dTLB-loads will-it-scale.per_process_ops 1.7e+07 +-+--------------------------------------------------------------+ |.+.+..+. .+. .+.+..+.+.+.+.+.+..+.+.+.+.+.+..+.+.+.+.+.+.. | 1.65e+07 +-+ + + +.+.+.| 1.6e+07 +-+ | | | 1.55e+07 +-+ | 1.5e+07 +-+ | | | 1.45e+07 +-+ | 1.4e+07 +-+ | | | 1.35e+07 +-+ | 1.3e+07 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 | 1.25e+07 +-+--------------------------------------------------------------+ perf-stat.instructions 1.4e+13 +-+--------------------------------------------------------------+ | .+.. .+. .+. | 1.35e+13 +-+ .+. .+. .+ + +.+.+.+..+ +.+.+.+..+.+.+.| |.+.+..+.+.+.+ +..+ +.+ | | | 1.3e+13 +-+ | | | 1.25e+13 +-+ | | | 1.2e+13 +-+ | | O O | O O O O O O O O O O O O O O O O O O | 1.15e+13 +-+ O O O O O O O | | | 1.1e+13 +-+--------------------------------------------------------------+ perf-stat.branch-instructions 3.2e+12 +-+---------------------------------------------------------------+ | .+. .+. .+ .+. | 3.1e+12 +-+.+.. .+ +. .+. .+. +..+ + + .+ +.+. | |.+ + +. + +.+.. + +. +..+. | 3e+12 +-+ .+. .+ +.| | + + | 2.9e+12 +-+ | | | 2.8e+12 +-+ | | | 2.7e+12 +-+ O O O O O O O | | O O O O O O O O O O O O | 2.6e+12 O-+ O O O O O O O | | | 2.5e+12 +-+---------------------------------------------------------------+ perf-stat.branch-misses 1.2e+11 +-+---------------------------------------------------------------+ | | 1e+11 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 | | | 8e+10 +-+ | | | 6e+10 +-+ | | | 4e+10 +-+ | | | | | 2e+10 +-+ | | | 0 +-+---------------------------------------------------------------+ perf-stat.dTLB-stores 3e+12 +-+---------------------------------------------------------------+ | .+. .+ | 2.9e+12 +-+ + + : | | : : | 2.8e+12 +-+ : : | | : : .+.+ | 2.7e+12 +-+ : : .+ .+. :| | .+.. .+. .+.. .+.+.+. : : .+.+.+.+..+ + .+ :| 2.6e+12 +-+ +.+ + + + +..+ + | | | 2.5e+12 +-+ | | | 2.4e+12 +-+ O O O | | O O O O O O O O O O O O O O O O O O O | 2.3e+12 O-+---------------------O----O-----O--------O---------------------+ perf-stat.branch-miss-rate_ 4 +-+-------------------------------------------------------------------+ 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 | 3.5 +-+ | 3 +-+ | | | 2.5 +-+ | | | 2 +-+ | | | 1.5 +-+ | 1 +-+ | | | 0.5 +-+ | | | 0 +-+-------------------------------------------------------------------+ perf-stat.ipc 0.86 +-+------------------------------------------------------------------+ | .+.. .+.+ .+.. | 0.84 +-+ .+.+.. .+ + + .+.+. .+.+.+..+.+.+ +.| 0.82 +-+..+. .+..+.+ +.+.+..+ +. +. | | + | 0.8 +-+ | | | 0.78 +-+ | | | 0.76 +-+ | 0.74 +-+ | | | 0.72 +-O O O O O O O O O O | O O O O O O O O O O O O O O | 0.7 +-+-------------O------O-O-------------------------------------------+ perf-stat.cpi 1.45 +-+------------------------------------------------------------------+ | O O | 1.4 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 | | | 1.35 +-+ | | | 1.3 +-+ | | | 1.25 +-+ | | | |.+.. .+.+..+.+. .+.+.+..+. .+.. .+.. .| 1.2 +-+ + +.+. +. .+. .+ +.+ +.+.+..+.+.+.+..+ | | +. + | 1.15 +-+------------------------------------------------------------------+ will-it-scale.time.user_time 580 +-+-------------------------------------------------------------------+ O O O | 560 +-+ O O O O O O O O O O O O O O O O O O | 540 +-+ O O O O O O | | | 520 +-+ | 500 +-+ | | | 480 +-+ .+.. | 460 +-+ +.+. .+ +.| |.+..+.+.+..+.+.+..+.+.+..+.+ + +..+.+.+..+.+.+..+ | 440 +-+ : + | 420 +-+ : .+. .+ | | +. + | 400 +-+-------------------------------------------------------------------+ will-it-scale.time.system_time 2100 +-+------------------------------------------------------------------+ | +.+..+.+ | 2080 +-+ + : | 2060 +-+..+.+. .+. .+..+. .+..+ : .+.+.+..+.+.+..+.+ | | +. +.+ + +.+. + | 2040 +-+ +.+..+.| 2020 +-+ | | | 2000 +-+ | 1980 +-+ | | O O O | 1960 +-+ O O O O O O O O O O O O O O O O O O O O | 1940 O-+ O O | | O | 1920 +-+------------------------------------------------------------------+ [*] bisect-good sample [O] bisect-bad sample 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. Thanks, Xiaolong