Hello all, I was recommended to post my observation to this mailing list; hope that this is appropriate. Since mid-March, my Tumbleweed suffers a drastic performance loss. I observed this during my work on MAME (the emulator framework) which is an application with high CPU load. For benchmark purposes, MAME offers a command line option that suppresses screen output and turns off real-time synchronization so that the emulator core is running at the maximum speed. Typically you should expect a multiple of the real speed, expressed by a percentage of far above 100%. At some time in mid-March, the benchmark speed for a selected system dropped from 900% to 300%, for another emulated system from 450% to 150%, which is already too low to ensure a full emulation speed with screen output. To rule out any effects from the MAME application, I have been using a version that I built almost a year ago, leaving it unchanged. The described slowdown occurs on three separate desktop PCs, which means that a hardware issue is unlikely. All PCs have a Core-i7 architecture. Interestingly, on two laptops that I could use to test, the effect does not occur. Consequently, this means that now my old laptop from 2012 with a Core i5-3320M@2.6 GHz runs MAME faster than my Core i7-6700K@4.0 GHz. The slowdown also occurs in other applications. Notably, the Leawo Bluray Player that runs in WINE is not able to sustain the frame rate any longer, delivering chopped replay, which was perfect before. During the last days I tried to bisect the kernel source from Github in order to isolate the point where the effect started (remote origin: git@github.com:openSUSE/kernel.git). Interestingly, the effect did not show up until 4.16.0-rc6, while that same desktop PC already showed the effect during the distro upgrade around 4.15.13 (which was in March). The result is: bad: 646d6e114288 Update to 4.16-rc6. good: aec6bb8e2770 - Refresh patches.suse/kernel-add-release-status-to-kernel-build.patch. If desired, I can give you a small bundle of the MAME executable to run the benchmark by yourself. Here is the effect: michael@capella:~/susekernel> uname -a Linux capella 4.16.0-rc5-1-default+ #26 SMP PREEMPT Sun Apr 22 14:26:13 CEST 2018 x86_64 x86_64 x86_64 GNU/Linux michael@capella:~/susekernel> git status HEAD detached at aec6bb8e2770 nothing to commit, working tree clean michael@capella:~/susekernel> cd ~/mame michael@capella:~/mame> ./mame64_0186 ti99_4a -bench 20 Average speed: 883.31% (19 seconds) michael@capella:~/mame> michael@capella:~/susekernel> uname -a Linux capella 4.16.0-rc6-1-default+ #27 SMP PREEMPT Sun Apr 22 16:17:52 CEST 2018 x86_64 x86_64 x86_64 GNU/Linux michael@capella:~/susekernel> git status HEAD detached at 646d6e114288 nothing to commit, working tree clean michael@capella:~/susekernel> cd ~/mame michael@capella:~/mame> ./mame64_0186 ti99_4a -bench 20 Average speed: 305.27% (19 seconds) michael@capella:~/mame> Greetings, Michael -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org