[sched,rcu] 9234566d3a3: +1.6% will-it-scale.scalability, +1302.6% time.involuntary_context_switches

[Jet Chen]

Hi Paul,

we noticed the below changes on
git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git torture.2014.04.18a
commit 9234566d3a36c0aead8852e3c2ca94cd8ebfe219 ("sched,rcu: Make cond_resched() report RCU quiescent states")

Comparison 1 - parent commit of 9234566d3a36c0aead8852e3c2ca94cd8ebfe219 vs 9234566d3a36c0aead8852e3c2ca94cd8ebfe219

e119454e74a852f  9234566d3a36c0aead8852e3c
---------------  -------------------------
    1035948 ~ 0%      +1.6%    1052990 ~ 0%  TOTAL will-it-scale.per_thread_ops
    1271322 ~ 0%      +1.8%    1294004 ~ 0%  TOTAL will-it-scale.per_process_ops
       0.63 ~ 0%      -5.2%       0.60 ~ 0%  TOTAL will-it-scale.scalability
      22470 ~ 2%   +1302.6%     315168 ~ 2%  TOTAL time.involuntary_context_switches
      84265 ~ 5%   +1047.1%     966581 ~ 1%  TOTAL interrupts.IWI
       1828 ~44%    +189.6%       5295 ~13%  TOTAL time.voluntary_context_switches
       5337 ~ 1%     +82.1%       9720 ~ 1%  TOTAL vmstat.system.cs
     118599 ~ 0%     -30.4%      82545 ~ 0%  TOTAL interrupts.0:IO-APIC-edge.timer
     224021 ~ 4%     +34.7%     301858 ~ 2%  TOTAL interrupts.RES
      25148 ~ 0%      +7.0%      26917 ~ 0%  TOTAL vmstat.system.in
    7063439 ~ 0%      -5.2%    6694536 ~ 0%  TOTAL interrupts.LOC
     188866 ~ 0%      -3.1%     183008 ~ 0%  TOTAL interrupts.NMI
     188866 ~ 0%      -3.1%     183008 ~ 0%  TOTAL interrupts.PMI
       3720 ~ 0%      -1.5%       3665 ~ 0%  TOTAL time.system_time
       1215 ~ 0%      -1.4%       1198 ~ 0%  TOTAL time.percent_of_cpu_this_job_got


Comparison 2 - b84c4e08143c98dad4b4d139f08db0b98b0d3ec4 vs 9234566d3a36c0aead8852e3c2ca94cd8ebfe219

Fengguang has reported stats changes about b84c4e08143c98dad4b4d139f08db0b98b0d3ec4 to you days ago.
git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git dev.2014.04.14a
commit b84c4e08143c98dad4b4d139f08db0b98b0d3ec4 ("sched,rcu: Make cond_resched() report RCU quiescent states")

Let's have a compare here.

b84c4e08143c98d  9234566d3a36c0aead8852e3c
---------------  -------------------------
     809309 ~ 0%      -2.6%     788400 ~ 0%  TOTAL will-it-scale.per_process_ops
       0.61 ~ 0%      -1.9%       0.60 ~ 0%  TOTAL will-it-scale.scalability
     434080 ~ 0%      -1.5%     427643 ~ 0%  TOTAL will-it-scale.per_thread_ops
          4 ~11%  +1.2e+05%       5249 ~ 2%  TOTAL interrupts.IWI
        607 ~ 7%     +28.0%        778 ~14%  TOTAL interrupts.47:PCI-MSI-edge.eth0
      12349 ~ 2%     -14.6%      10548 ~ 1%  TOTAL interrupts.0:IO-APIC-edge.timer
       3078 ~ 3%     +20.9%       3722 ~ 6%  TOTAL interrupts.RES


Comparison 3 - parent commit of b84c4e08143c98dad4b4d139f08db0b98b0d3ec4 vs b84c4e08143c98dad4b4d139f08db0b98b0d3ec4

Duplicated with Fengguang's report. Help you to see these info in a page :)

ad86a04266f9b49  b84c4e08143c98dad4b4d139f
---------------  -------------------------
     676264 ~ 0%      +3.3%     698461 ~ 0%  TOTAL will-it-scale.per_thread_ops
    1174547 ~ 0%      +3.0%    1209307 ~ 0%  TOTAL will-it-scale.per_process_ops
       1.67 ~ 0%      -2.3%       1.63 ~ 0%  TOTAL will-it-scale.scalability
      10522 ~ 2%    +921.2%     107463 ~ 1%  TOTAL time.involuntary_context_switches
      77671 ~ 3%     +67.0%     129688 ~ 3%  TOTAL interrupts.RES
      99502 ~ 0%     -27.8%      71813 ~ 0%  TOTAL interrupts.0:IO-APIC-edge.timer
       2554 ~ 0%     +49.1%       3809 ~ 1%  TOTAL vmstat.system.cs
      11524 ~ 0%      -2.3%      11259 ~ 0%  TOTAL vmstat.system.in
        213 ~ 0%      -4.3%        204 ~ 0%  TOTAL time.system_time
         74 ~ 0%      -4.1%         71 ~ 0%  TOTAL time.percent_of_cpu_this_job_got
    3495099 ~ 0%      -3.1%    3387173 ~ 0%  TOTAL interrupts.LOC




Thanks,
Jet



./runtest.py open2 32 1 4 6 8