Re: 6.10/regression/bisected - after f1d97e769152 I spotted increased execution time of the kswapd0 process and symptoms as if there is not enough memory

From: Andrea Gelmini
Date: Wed Jul 03 2024 - 17:08:22 EST


Il giorno mer 3 lug 2024 alle ore 13:59 Filipe Manana
<fdmanana@xxxxxxxxxx> ha scritto:
>
> I'm collecting all the patches in this branch:
>
> https://git.kernel.org/pub/scm/linux/kernel/git/fdmanana/linux.git/log/?h=em_shrinker_6.10
>
> They apply cleanly to 6.10-rc.

Yeap, as I wrote before, same problem here.
I tried the branch over today Linus git (master), and nothing changed.
But, good news, I can provide a few more details.

So, no need to use restic. On my laptop (nvme + ssd, 32GB RAM, Lenovo T480):
a) boot up;
b) just open Window Maker and two Konsole, one with htop (with a few
tricks to view PSI and so on);
c) on one terminal run: tar cp /home/ | pv > /dev/null
d) wait less than one minutes, and I see "PSI full memory" increase
more than 50, memory pressure on swap, and two CPU threads (out of
eight) busy at 100%;
e) system get sluggish (on htop I see no process eating CPU);
f) if I kill tar, PSI memory keeps going up and down, so the threads.
After lots of minutes, everything get back to no activity. In these
minutes I see by iotop there's no activity nor on ssd or nvme. Until
the end, the system is unresponsive, oh well, really slow.

My / is BTRFS. Not many years of aging. Usually with daily snapshots
and forced compression.

Less than 4.000.000 files on the system. Usually .git and source code.

root@glen:/home/gelma# btrfs filesystem usage /
Overall:
Device size: 3.54TiB
Device allocated: 2.14TiB
Device unallocated: 1.40TiB
Device missing: 0.00B
Device slack: 0.00B
Used: 2.03TiB
Free (estimated): 1.50TiB (min: 1.50TiB)
Free (statfs, df): 1.50TiB
Data ratio: 1.00
Metadata ratio: 1.00
Global reserve: 512.00MiB (used: 0.00B)
Multiple profiles: no

Data,single: Size:2.12TiB, Used:2.02TiB (95.09%)
/dev/mapper/sda6_crypt 2.12TiB

Metadata,single: Size:16.00GiB, Used:14.73GiB (92.04%)
/dev/mapper/sda6_crypt 16.00GiB

System,single: Size:32.00MiB, Used:320.00KiB (0.98%)
/dev/mapper/sda6_crypt 32.00MiB

Unallocated:
/dev/mapper/sda6_crypt 1.40TiB