Re: [PATCH v2 0/4] Utilization estimation (util_est) for FAIR tasks

From: Mike Galbraith
Date: Wed Dec 13 2017 - 12:57:43 EST

On Tue, 2017-12-05 at 17:10 +0000, Patrick Bellasi wrote:
> This is a respin of:
> https://lkml.org/lkml/2017/11/9/546
> which has been rebased on v4.15-rc2 to have util_est now working on top
> of the recent PeterZ's:
> [PATCH -v2 00/18] sched/fair: A bit of a cgroup/PELT overhaul
>
> The aim of this series is to improve some PELT behaviors to make it a
> better fit for the scheduling of tasks common in embedded mobile
> use-cases, without affecting other classes of workloads.

I thought perhaps this patch set would improve the below behavior, but
alas it does not.  That's 3 instances of firefox playing youtube clips
being shoved into a corner by hogs sitting on 7 of 8 runqueues.  PELT
serializes the threaded desktop, making that threading kinda pointless,
and CFS not all that fair.

6569 root 20 0 4048 704 628 R 100.0 0.004 5:10.48 7 cpuhog
6573 root 20 0 4048 712 636 R 100.0 0.004 5:07.47 5 cpuhog
6581 root 20 0 4048 696 620 R 100.0 0.004 5:07.36 1 cpuhog
6585 root 20 0 4048 812 736 R 100.0 0.005 5:08.14 4 cpuhog
6589 root 20 0 4048 712 636 R 100.0 0.004 5:06.42 6 cpuhog
6577 root 20 0 4048 720 644 R 99.80 0.005 5:06.52 3 cpuhog
6593 root 20 0 4048 728 652 R 99.60 0.005 5:04.25 0 cpuhog
6755 mikeg 20 0 2714788 885324 179196 S 19.96 5.544 2:14.36 2 Web Content
6620 mikeg 20 0 2318348 312336 145044 S 8.383 1.956 0:51.51 2 firefox
3190 root 20 0 323944 71704 42368 S 3.194 0.449 0:11.90 2 Xorg
3718 root 20 0 3009580 67112 49256 S 0.599 0.420 0:02.89 2 kwin_x11
3761 root 20 0 769760 90740 62048 S 0.399 0.568 0:03.46 2 konsole
3845 root 9 -11 791224 20132 14236 S 0.399 0.126 0:03.00 2 pulseaudio
3722 root 20 0 3722308 172568 88088 S 0.200 1.081 0:04.35 2 plasmashel

------------------------------------------------------------------------------------------------------------------------------------
Task | Runtime ms | Switches | Average delay ms | Maximum delay ms | Sum delay ms | Maximum delay at |
------------------------------------------------------------------------------------------------------------------------------------
Web Content:6755 | 2864.862 ms | 7314 | avg: 0.299 ms | max: 40.374 ms | sum: 2189.472 ms | max at: 375.769240 |
Compositor:6680 | 1889.847 ms | 4672 | avg: 0.531 ms | max: 29.092 ms | sum: 2478.559 ms | max at: 375.759405 |
MediaPl~back #3:(13) | 3269.777 ms | 7853 | avg: 0.218 ms | max: 19.451 ms | sum: 1711.635 ms | max at: 391.123970 |
MediaPl~back #4:(10) | 1472.986 ms | 8189 | avg: 0.236 ms | max: 18.653 ms | sum: 1933.886 ms | max at: 376.124211 |
MediaPl~back #1:(9) | 601.788 ms | 6598 | avg: 0.247 ms | max: 17.823 ms | sum: 1627.852 ms | max at: 401.122567 |
firefox:6620 | 303.181 ms | 6232 | avg: 0.111 ms | max: 15.602 ms | sum: 691.865 ms | max at: 385.078558 |
Socket Thread:6639 | 667.537 ms | 4806 | avg: 0.069 ms | max: 12.638 ms | sum: 329.387 ms | max at: 380.827323 |
MediaPD~oder #1:6835 | 154.737 ms | 1592 | avg: 0.700 ms | max: 10.139 ms | sum: 1113.688 ms | max at: 392.575370 |
MediaTimer #1:6828 | 42.660 ms | 5250 | avg: 0.575 ms | max: 9.845 ms | sum: 3018.994 ms | max at: 380.823677 |
MediaPD~oder #2:6840 | 150.822 ms | 1583 | avg: 0.703 ms | max: 9.639 ms | sum: 1112.962 ms | max at: 380.823741 |
...