Re: [PATCH 00/18 v2] Improving latency of short slice tasks
From: Kayra Cizmeci
Date: Thu Oct 08 2026 - 15:14:30 EST
Hi All,
I wanted to ran some tests for this patch series. I couldn't really
apply it without some issues, but I think I managed to apply
it cleanly this time... Tho I may have been doing something wrong.
Please let me know if so.
base: 4a3b51aab6e25244d97936aa65e6d5425adf98e1 (on tip/sched/core)
Command Used Each Run:
hackbench -g 4 -l 100000 > /dev/null & sudo chrt -o -T 300000 0 ~/rt-tests/cyclictest --policy=other -t 1 -i 1000 -D 20 -q -m; wait
Environment:
Zen 3 with 8 Cores and 16 Threads. And Fedora.
THE RESULTS (COOKED):
On Base in 5 runs, average values are: Min: 3.8, Act: 5.8, Avg: 8.8 and
Max: 2511.6 (I need tea.)
On Base + Patches in 5 runs, average values bla bla you get it:
Min 4, Act: 5.8, Avg: 7.2 and Max: 1781.6
Or, in the shape of art made with love and passion:
+------BASE-----+--PATCHED--+
| MIN 3.8 | 4 |
| ACT 5.8 | 5.8 |
| AVG 8.8 | 7.2 |
| MAX 2511.6 | 1781.6 |
+--------------+------------+
Hmhp... Hope I'm not missing something. I need water. Bah.
Tested-by: Kayra Cizmeci <kayracizmeci@xxxxxxxxx>
Dancing donkey chases a car while shouting "Linux is the best, my dancing is the coolest. Cry."
Thanks,
Kayra
I'll add other not too important things below, these are pretty raw.
But if you wanna have a look you can.
THE RESULTS (RAW):
BASE 7.3.0-rc1+ #2:
RUN 1:
[1] 1950
# /dev/cpu_dma_latency set to 0us
T: 0 ( 2115) P: 0 I:1000 C: 19990 Min: 4 Act: 6 Avg: 8 Max: 1885
[1]+ Done hackbench -g 4 -l 100000 > /dev/null
RUN 2:
[1] 2132
# /dev/cpu_dma_latency set to 0us
T: 0 ( 2297) P: 0 I:1000 C: 19990 Min: 4 Act: 6 Avg: 9 Max: 2695
[1]+ Done hackbench -g 4 -l 100000 > /dev/null
linuxfucks@micro-softly:~$ (Opsies. Who's hostname is this? It's so cool. Wow. 'linuxfucks')
RUN 3:
[1] 2307
# /dev/cpu_dma_latency set to 0us
T: 0 ( 2472) P: 0 I:1000 C: 19988 Min: 4 Act: 5 Avg: 8 Max: 3246
[1]+ Done hackbench -g 4 -l 100000 > /dev/null
RUN 4:
[1] 2493
# /dev/cpu_dma_latency set to 0us
T: 0 ( 2658) P: 0 I:1000 C: 19995 Min: 3 Act: 6 Avg: 9 Max: 1991
[1]+ Done hackbench -g 4 -l 100000 > /dev/null
RUN 5:
[1] 2671
# /dev/cpu_dma_latency set to 0us
T: 0 ( 2836) P: 0 I:1000 C: 19992 Min: 4 Act: 6 Avg: 10 Max: 2741
[1]+ Done hackbench -g 4 -l 100000 > /dev/null
BASE + PATCHES 7.3.0-rc1+ #3:
RUN 1:
[1] 1490
# /dev/cpu_dma_latency set to 0us
T: 0 ( 1657) P: 0 I:1000 C: 19993 Min: 4 Act: 5 Avg: 7 Max: 3091
[1]+ Done hackbench -g 4 -l 100000 > /dev/null
RUN 2:
[1] 1671
# /dev/cpu_dma_latency set to 0us
T: 0 ( 1836) P: 0 I:1000 C: 19999 Min: 4 Act: 6 Avg: 7 Max: 1529
[1]+ Done hackbench -g 4 -l 100000 > /dev/null
RUN 3:
[1] 1848
# /dev/cpu_dma_latency set to 0us
T: 0 ( 2013) P: 0 I:1000 C: 19998 Min: 4 Act: 6 Avg: 7 Max: 1455
[1]+ Done hackbench -g 4 -l 100000 > /dev/null
RUN 4:
[1] 2023
# /dev/cpu_dma_latency set to 0us
T: 0 ( 2188) P: 0 I:1000 C: 19995 Min: 4 Act: 6 Avg: 7 Max: 1524
[1]+ Done hackbench -g 4 -l 100000 > /dev/null
RUN 5:
[1] 2200
# /dev/cpu_dma_latency set to 0us
T: 0 ( 2365) P: 0 I:1000 C: 19989 Min: 4 Act: 6 Avg: 8 Max: 1309
[1]+ Done hackbench -g 4 -l 100000 > /dev/null