http://bugzilla.opensuse.org/show_bug.cgi?id=1039768 Bug ID: 1039768 Summary: Failure to reduce frequency at low workload Classification: openSUSE Product: openSUSE Tumbleweed Version: Current Hardware: x86-64 OS: Other Status: NEW Severity: Normal Priority: P5 - None Component: Basesystem Assignee: bnc-team-screening@forge.provo.novell.com Reporter: mpaton2000@gmail.com QA Contact: qa-bugs@suse.de Found By: --- Blocker: --- Hardware is ASUS Laptop with Intel Core M3-6Y30 CPU, 8GB, passive cooling. Base frequency=900MHz, Max Turbo=2.2GHz. Minimum frequency 400MHz. Installed Tumbleweed x86_64 in December 2016, KDE desktop, btrfs root fs, no extra repositories. Problem is that after boot to KDE desktop, after initial set of root owned housekeeping tasks finishes, and system workload goes down to less than 3% on each core (from top and ksysguard), (2 physical cores, hyperthreaded), frequency remains at around Max turbo, typically 2.2HGz on one core and 2.0GHz on the other. Core temps stay high, and battery life halves. I selected Tumbleweed in the hope of using the advanced power saving features that this processor offers. By chance, I discovered that when I boot from hibernation, a similar set of root owned housekeeping runs, and then frequencies reduce to typically around 500MHz, with occasional brief spikes to 100MHz on a single core. This told me that the kernel and the processor could indeed cooperate on selecting a low frequency, as intended. However,something was being done on return from hibernation that wasn't being done on initial boot, in order to enable this behaviour. This behaviour remained constant all the way through the 4.10.13 kernel. -- You are receiving this mail because: You are on the CC list for the bug.