Linux 4.20 Showing Some Performance Slowdowns

[phoronix]

Phoronix: Linux 4.20 Showing Some Performance Slowdowns

Being well past the Linux 4.20 merge window I have moved onto benchmarking more of this development version of the Linux kernel. Unfortunately, there are some clear performance regressions...

http://www.phoronix.com/scan.php?page=news_item&px=Linux-4.20-Initial-Slowdowns

[perpetually high]

It's almost as if the kernel was....... stoned on a few of those tests. I'll see myself out.

No but seriously, is it too late to change the name from "People's Front" to "Dude, Where's My Kernel?"

[Xaero_Vincent]

Guess I'll be sticking with 4.19 LTS for awhile then.

[dungeon]

Guess I'll be sticking with 4.19 LTS for awhile then.

Yeah Debian would stick with that for next 5-6 years for Buster, so there is no reason to hurry.

Also i heard today that bearded Mark announced 10 years of support for Ubuntu 18.04

https://www.serverwatch.com/server-n...-10-years.html

Same like with Debian ELTS these from CIP also pushing there and wanna up to 10 (or to say 5+5) years extended a la Windows

[dungeon]

I tested latest AMD drmp-next-4.21-wip kernel and the system had a corrupted screen and no response to the mouse clicks when unzipping the Linux kernel tar ball. Had a orphaned journal file system and next boot took long time because disk fixing was running.

Report that to AMD and that is it

I have same FGLRX version working from 2.6.32 kernels up to current 4.19 (basically anything in last 9 years) so normal kernels are fine - drivers might not at random rolling point of choice xyz

[perpetually high]

I believe those file system bugs are related to the 4.20 kernel, not AMD.

Had issues on 4.20 with both -rc1 and -rc2 where the EXT4 file system became scewy and needed a manual fsck when it went directly into the initramfs prompt on reboot. Wasn't sure if it was related to RAID or not. Everything was fine after running fsck and fixing the errors and doesn't seem to linger after. Another user mentioned xfs issues, so I'd stay weary on the 4.20 kernels right now unless you're willing to report back/handle instability issues.

I'm compiling drm-fixes-4.20 right now myself. I've tried both amd-staging-drm-next and drm-next-4.21-wip and they both introduced a bug that was fixed in 4.20 (144 hz display bug), but was present in 4.19. I'm confused why the AMD branches have the bug still when they're based off 4.20-rc1, so I'm giving drm-fixes-4.20 a whirl and hoping that has the fix in there.

EDIT: Ah-ha! No 144hz display bug in this branch!

$ uname -a
Linux ubuntu 4.20.0-042000rc1+drm-fixes-4.20-generic #201811120835 SMP PREEMPT Thu Nov 15 22:33:11 PST 2018 x86_64 x86_64 x86_64 GNU/Linux

I'm gonna bisect that bad boy and put an end to this madness! I will be your champion 144hz display folks! We're bringing the fix to 4.19 LTS!!

[dungeon]

Yeah, these 240/144 Hz are sexy better than 4K 60Hz for gaming

Or at least for some gaming really and of course if average gaming Joe could even notice it... i can't notice difference too

Probably because i was playing a lot on PS4, where some games are even capped at 30 fps... who knows, maybe that is the reason

[dungeon]

OK, you said "system had a corrupted screen" so i tought maybe it is bug in GPU driver too

[towo2099]

The kernel 14.9.0 from kernel.org is stable.

Wow, i would like to have this kernel too.

[nanonyme]

Yeah Debian would stick with that for next 5-6 years for Buster, so there is no reason to hurry.

Also i heard today that bearded Mark announced 10 years of support for Ubuntu 18.04

https://www.serverwatch.com/server-n...-10-years.html

Same like with Debian ELTS these from CIP also pushing there and wanna up to 10 (or to say 5+5) years extended a la Windows

I guess it's a pretty good thing then that Flatpak 1.0 was pushed as update for it so people won't keep using 0.11 for that whole time