[regression] gnome-shell stutters noticeably with kernel 5.8.0-19, but not 5.8.0-18

[Daniel van Vugt]

gnome-shell stutters noticeably with kernel 5.8.0-19

I've now tested four recent kernels:

5.8.0-20: stutters
5.8.0-19: stutters
5.8.0-18: smooth
5.8.0-16: smooth

ProblemType: Bug
DistroRelease: Ubuntu 20.10
Package: linux-image-5.8.0-19-generic 5.8.0-19.20
ProcVersionSignature: Ubuntu 5.8.0-19.20-generic 5.8.8
Uname: Linux 5.8.0-19-generic x86_64
ApportVersion: 2.20.11-0ubuntu48
Architecture: amd64
CasperMD5CheckResult: skip
Date: Wed Sep 30 13:52:38 2020
InstallationDate: Installed on 2020-07-16 (76 days ago)
InstallationMedia: Ubuntu 20.10 "Groovy Gorilla" - Alpha amd64 (20200507)
Lsusb:
 Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
 Bus 001 Device 004: ID 17ef:6009 Lenovo ThinkPad Keyboard with TrackPoint
 Bus 001 Device 003: ID 045e:0823 Microsoft Corp. Classic IntelliMouse
 Bus 001 Device 002: ID 8087:0a2b Intel Corp. Bluetooth wireless interface
 Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
MachineType: LENOVO 10M7CTO1WW
ProcEnviron:
 LANGUAGE=en_AU:en
 TERM=xterm-256color
 PATH=(custom, no user)
 LANG=en_AU.UTF-8
 SHELL=/bin/bash
ProcFB: 0 i915drmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-5.8.0-19-generic root=UUID=21e70a66-4d0f-49fc-b42c-668fc1594d91 ro quiet splash vt.handoff=7
PulseList: Error: command ['pacmd', 'list'] failed with exit code 1: No PulseAudio daemon running, or not running as session daemon.
RelatedPackageVersions:
 linux-restricted-modules-5.8.0-19-generic N/A
 linux-backports-modules-5.8.0-19-generic N/A
 linux-firmware 1.190
SourcePackage: linux
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 02/06/2018
dmi.bios.release: 0.47
dmi.bios.vendor: LENOVO
dmi.bios.version: M16KT47A
dmi.board.name: 3102
dmi.board.vendor: LENOVO
dmi.board.version: SDK0J40709 WIN 3259627060530
dmi.chassis.type: 3
dmi.chassis.vendor: LENOVO
dmi.chassis.version: None
dmi.modalias: dmi:bvnLENOVO:bvrM16KT47A:bd02/06/2018:br0.47:svnLENOVO:pn10M7CTO1WW:pvrThinkCentreM710s:rvnLENOVO:rn3102:rvrSDK0J40709WIN3259627060530:cvnLENOVO:ct3:cvrNone:
dmi.product.family: ThinkCentre M710s
dmi.product.name: 10M7CTO1WW
dmi.product.sku: LENOVO_MT_10M7_BU_Think_FM_ThinkCentre M710s
dmi.product.version: ThinkCentre M710s
dmi.sys.vendor: LENOVO

[Ubuntu Kernel Bot (ubuntu-kernel-bot)]

This change was made by a bot.

[Daniel van Vugt (vanvugt)]

When finished, this will also solve it:

  https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1441

but that probably won't be this cycle.

[Daniel van Vugt (vanvugt)]

Workaround:

sudo -s
for g in /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor ; do
  echo performance > $g
done

[Daniel van Vugt (vanvugt)]

And another workaround:

cd /sys/class/drm/card0
sudo cp gt_max_freq_mhz gt_min_freq_mhz

[Daniel van Vugt (vanvugt)]

Something (not the kernel) changed over the weekend and now the stutter seems to be gone...?

[Carlos Pita (carlosjosepita)]

I'm not sure what are you using as energy_performance_preference but I've seen important improvements in scaling speed when using balance_performance instead of balance_power, without the need to set the governor to full performance. I'm in Arch at this moment and can't remember if Ubuntu defaults to balance_performance or balance_power, though.

[Carlos Pita (carlosjosepita)]

FWIW today 3.38 was released to Arch stable repo and I tested it using kernel 5.8.10 and 5.8.13. For the same governor, energy performance and gpu min freq settings, stuttering in the overview has increased a bit (HiDPI screen & 620, I think you already know that at this point). Anyway I've seen many fluctuations since 3.34 when using different kernels so it doesn't surprise me, seems like subtle timing issues that probably won't be 100% fixed by freq scaling alone but also by the additional buffering provided by !1441. Will take a look at Ubuntu beta this weekend and let you know about my experience there.

[Launchpad Janitor (janitor)]

[Expired for linux (Ubuntu) because there has been no activity for 60 days.]