FYI, we noticed the below changes on

git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git sched/core
commit 638476007d13534b2ed4134bf0279ef44071140b ("sched/fair: Fix the dealing with decay_count in __synchronize_entity_decay()")

It appears that your patch cause CPU usage increased a little, so that unixbench score increased.

testbox/testcase/testparams: nhm-white/unixbench/spawn

7f1a169b88f513e3  638476007d13534b2ed4134bf0  
----------------  --------------------------  
         %stddev     %change         %stddev
             \          |                \  
    268908 ±  0%      +4.6%     281320 ±  0%  unixbench.time.involuntary_context_switches
 1.147e+08 ±  0%      +1.5%  1.164e+08 ±  0%  unixbench.time.minor_page_faults
      3607 ±  0%      +1.1%       3648 ±  0%  unixbench.score
       324 ±  0%      +1.2%        328 ±  0%  unixbench.time.percent_of_cpu_this_job_got
       633 ±  0%      +1.2%        641 ±  0%  unixbench.time.system_time
     54100 ±  3%     +51.0%      81705 ± 21%  sched_debug.cpu#4.ttwu_local
     65678 ±  7%     +49.5%      98187 ± 16%  sched_debug.cpu#6.ttwu_local
      5624 ± 31%     +52.1%       8553 ± 11%  sched_debug.cpu#6.curr->pid
        58 ± 20%     +37.6%         80 ±  7%  sched_debug.cfs_rq[3]:/.runnable_load_avg
        61 ± 10%     +22.5%         74 ± 14%  sched_debug.cpu#2.cpu_load[3]
    218479 ±  5%     +15.4%     252190 ±  5%  sched_debug.cpu#6.ttwu_count
       102 ± 17%     -19.3%         82 ± 10%  sched_debug.cpu#4.cpu_load[2]
    423974 ±  4%     +15.6%     490072 ±  5%  sched_debug.cpu#5.avg_idle
        62 ±  4%     +16.9%         72 ±  9%  sched_debug.cpu#2.cpu_load[4]
    152298 ±  2%      +9.7%     167037 ±  3%  sched_debug.cfs_rq[5]:/.min_vruntime
    156795 ±  1%     +11.3%     174544 ±  1%  sched_debug.cfs_rq[7]:/.min_vruntime
    155535 ±  3%     +11.8%     173813 ±  2%  sched_debug.cfs_rq[6]:/.min_vruntime
      9231 ±  0%      +1.3%       9348 ±  0%  vmstat.system.in

nhm-white: Nehalem
Memory: 6G


                            unixbench.time.system_time

  643 ++---------------------------------------------------------------O----+
  642 ++                    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 |
  641 ++                           O           O         O           O      |
  640 ++                                                                    |
      |                                                                     |
  639 ++                                                                    |
  638 ++                                                                    |
  637 ++                                                                    |
      |                                                                     |
  636 ++                                                                    |
  635 ++         .*                                                         |
      *.*.. .*..*  +         .*.. .*.*..  *                                 |
  634 ++   *        *..*.*..*    *       +                                  |
  633 ++--------------------------------*-----------------------------------+


                     unixbench.time.involuntary_context_switches

  286000 ++-----------------------------------------------------------------+
  284000 ++                                                 O               |
         |                                                    O    O        |
  282000 ++                                                          O O    O
  280000 O+O    O          O      O      O  O   O  O O    O     O         O |
         |    O      O O O           O O      O        O                    |
  278000 ++       O           O O                                           |
  276000 ++                                                                 |
  274000 ++                                                                 |
         |                                                                  |
  272000 ++                                                                 |
  270000 ++  .*.*.              *.*..      .*                               |
         *.*.     *..*. .*     :     *.*.*.                                 |
  268000 ++            *  +    :                                            |
  266000 ++----------------*--*---------------------------------------------+


                       kmsg.tsc:Fast_TSC_calibration_failed

    1 ++-------------------------------------O--------O---------------------+
      |                                                                     |
      |                                                                     |
  0.8 ++                                                                    |
      |                                                                     |
      |                                                                     |
  0.6 ++                                                                    |
      |                                                                     |
  0.4 ++                                                                    |
      |                                                                     |
      |                                                                     |
  0.2 ++                                                                    |
      |                                                                     |
      |                                                                     |
    0 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-O

        [*] bisect-good sample
        [O] bisect-bad  sample

To reproduce:

        apt-get install ruby ruby-oj
        git clone git://git.kernel.org/pub/scm/linux/kernel/git/wfg/lkp-tests.git
        cd lkp-tests
        bin/setup-local job.yaml # the job file attached in this email
        bin/run-local   job.yaml


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,
Huang, Ying