What else is needed here? -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to thermald in Ubuntu. https://bugs.launchpad.net/bugs/1874933
Title: Performance workaround for Dell 7390 2-in-1 Ice Lake Status in thermald package in Ubuntu: Fix Released Status in thermald source package in Focal: Incomplete Bug description: == SRU justification focal == As reported here: https://www.phoronix.com/forums/forum/linux-graphics-x-org-drivers/intel-linux/1174225-dell-xps-7390-intel-ice-lake-performance-hit-hard-by-a-linux-kernel-regression?view=stream This primarily impacts "Ubuntu 20.04 LTS (Focal Fossa)." as it switched to 5.4 kernel. The 5.4 kernel added support for "Processor thermal device", for Ice Lake, which will expose the power tables (via PPCC). This system default "max RAPL long term power limit" is 15W. But this power table is specifying as 9W. So thermald will limit power to 9W. If dptfxtract is executed, then power limit will be higher than power up value, but most of the users will use out of the box setup. So this need a workaround. This workaround will ignore any power limit less than the power up power limit. This is addressed in thermald 2.1 with two commits: https://github.com/intel/thermal_daemon/commit/f7db434293387c965e8d9141608f855893740e3a https://github.com/intel/thermal_daemon/commit/c3461690eafb7304bf59a39fb02955a5154b3861 I know 20.04 LTS uses 1.9.1. I can assist in backport if required. == Fix == Two upstream commits to ease backporting: - eeadf7d2efe Restore to min state on deactivation without depending on hardware state - 9a6dc27879a Clean up the code and documentation Two upstream commits for the fix: - f7db4342933 Avoid polling power in non PPCC case - c3461690eaf Ignore invalid PPCC max power limit == Test case == As reported here: https://www.phoronix.com/forums/forum/linux- graphics-x-org-drivers/intel-linux/1174225-dell-xps-7390-intel-ice- lake-performance-hit-hard-by-a-linux-kernel-regression?view=stream == Regression Potential == This fix involves changing the power limits logic so there is a potential that this may affect change the throttling behaviour of other systems with poorly defined PPCC power tables because it now ignores the power limits less than the power up limits. Users will see their machines run faster and hence active cooling may crank up (e.g. fans) but I think the speed improvement outweighs the noise factor. Note that these changes are already in thermald 2.1 that is now in Ubuntu Groovy 20.10. --------------------------- To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/thermald/+bug/1874933/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
