Re: [PATCH v2 19/19] sched/numa: Move task_placement closer to numa_migrate_preferred

From: Mel Gorman
Date: Thu Jun 21 2018 - 06:06:41 EST


On Wed, Jun 20, 2018 at 10:33:00PM +0530, Srikar Dronamraju wrote:
> numa_migrate_preferred is called periodically or when task preferred
> node changes. Preferred node evaluations happen once per scan sequence.
>
> If the scan completion happens just after the periodic numa migration,
> then we try to migrate to the preferred node and the preferred node might
> change, needing another node migration.
>
> Avoid this by checking for scan sequence completion only when checking
> for periodic migration.
>
> Running SPECjbb2005 on a 4 node machine and comparing bops/JVM
> JVMS LAST_PATCH WITH_PATCH %CHANGE
> 16 25862.6 26158.1 1.14258
> 1 74357 72725 -2.19482
>
> Running SPECjbb2005 on a 16 node machine and comparing bops/JVM
> JVMS LAST_PATCH WITH_PATCH %CHANGE
> 8 117019 113992 -2.58
> 1 179095 174947 -2.31
>
> (numbers from v1 based on v4.17-rc5)
> Testcase Time: Min Max Avg StdDev
> numa01.sh Real: 449.46 770.77 615.22 101.70
> numa01.sh Sys: 132.72 208.17 170.46 24.96
> numa01.sh User: 39185.26 60290.89 50066.76 6807.84
> numa02.sh Real: 60.85 61.79 61.28 0.37
> numa02.sh Sys: 15.34 24.71 21.08 3.61
> numa02.sh User: 5204.41 5249.85 5231.21 17.60
> numa03.sh Real: 785.50 916.97 840.77 44.98
> numa03.sh Sys: 108.08 133.60 119.43 8.82
> numa03.sh User: 61422.86 70919.75 64720.87 3310.61
> numa04.sh Real: 429.57 587.37 480.80 57.40
> numa04.sh Sys: 240.61 321.97 290.84 33.58
> numa04.sh User: 34597.65 40498.99 37079.48 2060.72
> numa05.sh Real: 392.09 431.25 414.65 13.82
> numa05.sh Sys: 229.41 372.48 297.54 53.14
> numa05.sh User: 33390.86 34697.49 34222.43 556.42
>
>
> Testcase Time: Min Max Avg StdDev %Change
> numa01.sh Real: 424.63 566.18 498.12 59.26 23.50%
> numa01.sh Sys: 160.19 256.53 208.98 37.02 -18.4%
> numa01.sh User: 37320.00 46225.58 42001.57 3482.45 19.20%
> numa02.sh Real: 60.17 62.47 60.91 0.85 0.607%
> numa02.sh Sys: 15.30 22.82 17.04 2.90 23.70%
> numa02.sh User: 5202.13 5255.51 5219.08 20.14 0.232%
> numa03.sh Real: 823.91 844.89 833.86 8.46 0.828%
> numa03.sh Sys: 130.69 148.29 140.47 6.21 -14.9%
> numa03.sh User: 62519.15 64262.20 63613.38 620.05 1.740%
> numa04.sh Real: 515.30 603.74 548.56 30.93 -12.3%
> numa04.sh Sys: 459.73 525.48 489.18 21.63 -40.5%
> numa04.sh User: 40561.96 44919.18 42047.87 1526.85 -11.8%
> numa05.sh Real: 396.58 454.37 421.13 19.71 -1.53%
> numa05.sh Sys: 208.72 422.02 348.90 73.60 -14.7%
> numa05.sh User: 33124.08 36109.35 34846.47 1089.74 -1.79%
>
> Signed-off-by: Srikar Dronamraju <srikar@xxxxxxxxxxxxxxxxxx>

Acked-by: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>

--
Mel Gorman
SUSE Labs