gamemode throttles (AMD?) CPUs on exit (powersave governor)

[Anjune M]

* Impact
The CPU governor is forced to 'powersave' when gamemode exists

* Test case
$ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
-> get the value
$ /usr/libexec/gamemode-simulate-game gedit
-> close gedit
$ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
-> the value should be the same as in the first step

* Regression potential
it's only a config change about the governer selection so it should have other impact

----------------------------------------

Release: Ubuntu Groovy Gorilla (development branch), but should be the same in 20.04
Package version: 1.5.1-0ubuntu3

What happens: The not-commented-out line "defaultgov=powersave" in /etc/gamemode.ini causes gamemode to switch to the powersave governor on exit rather than reverting to whatever governor was in use when gamemode kicked in. For AMD CPUs at least powersave is not an appropriate setting -- the CPU will run slow regardless of demand. It's nice for when you want some peace and quiet, not so nice for doing work (or for playing games you haven't configured to use gamemode).

What I expect to happen: Surely the sane, expected, and user-respecting behaviour here would be to return the system to the state it was in pre-gamemode?

[Sebastien Bacher (seb128)]

Thank you for your bug report, do you change the default mode in some way?
The request does make sense though but would be better reported upstream if you could send it there
https://github.com/FeralInteractive/gamemode

[Anjune M (anj-tuesday)]

I commented out the default governor setting in /etc/gamemode.ini so it'll revert to whatever governor was in use before gamemode. (It defaults to ondemand for me, and that seems like a good choice (that or schedutil) -- but I think whatever the system's default is, gamemode should revert to *it*, not to a preset choice of its own.)

I looked and it's already been reported upstream https://github.com/FeralInteractive/gamemode/issues/214
-- posted a comment there because it was considered "not a bug".

[Anjune M (anj-tuesday)]

PR submitted upstream.

[Stephan Lachnit (stephanlachnit)]

The PR was merged in upstream, I backported the fix to gamemode 1.5.1-3, which landed in Debian on Monday.
@seb128 you may want to drop or rebase the changes in the Ubuntu package. If everything goes right 1.5.1-4 should come around soon as well, so you might as well just wait for that.

[Launchpad Janitor (janitor)]

This bug was fixed in the package gamemode - 1.5.1-0ubuntu4

---------------
gamemode (1.5.1-0ubuntu4) groovy; urgency=medium

  * debian/patches/git_default_gov.patch:
    - revert to previous governor instead of "powersave" when exiting
      (lp: #1875740)

 -- Sebastien Bacher <email address hidden> Mon, 18 May 2020 15:05:23 +0200

[Steve Langasek (vorlon)]

Hello Anjune, or anyone else affected,

Accepted gamemode into focal-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/gamemode/1.5.1-0ubuntu3.1 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation on how to enable and use -proposed. Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested, what testing has been performed on the package and change the tag from verification-needed-focal to verification-done-focal. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-focal. In either case, without details of your testing we will not be able to proceed.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance for helping!

N.B. The updated package will be released to -updates after the bug(s) fixed by this package have been verified and the package has been in -proposed for a minimum of 7 days.

[Anjune M (anj-tuesday)]

1.5.1-0ubuntu3.1 fixes it for me on Kubuntu 20.04.

[Launchpad Janitor (janitor)]

This bug was fixed in the package gamemode - 1.5.1-0ubuntu3.1

---------------
gamemode (1.5.1-0ubuntu3.1) focal; urgency=medium

  * debian/patches/git_default_gov.patch:
    - revert to previous governor instead of "powersave" when exiting
      (lp: #1875740)

 -- Sebastien Bacher <email address hidden> Mon, 18 May 2020 15:05:23 +0200

[Brian Murray (brian-murray)]

The verification of the Stable Release Update for gamemode has completed successfully and the package is now being released to -updates. Subsequently, the Ubuntu Stable Release Updates Team is being unsubscribed and will not receive messages about this bug report. In the event that you encounter a regression using the package from -updates please report a new bug using ubuntu-bug and tag the bug report regression-update so we can easily find any regressions.