From Bugzilla Helper: User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.12) Gecko/20050922 Fedora/1.0.7-1.1.fc3 Firefox/1.0.7 Description of problem: Fedora Core 3: 2.6.9 kernel will allow you to modprobe -r powernow-k8. This allows you to stop the cpuspeed fluctuation without reboot. after upgrade to 2.6.12-1.1378_FC3 cannot modprobe -r powernow-k8. Can't stop cpuspeed without reboot. Doesn't matter if cpuspeed service is stopped or started. root@test:~$ modprobe -r powernow-k8 FATAL: Module powernow_k8 is in use. Version-Release number of selected component (if applicable): How reproducible: Always Steps to Reproduce: 1. Upgrade to 2.6.12-1.1378 kernel (smp or single proc) from 2.6.9 2. try to unload powernow-k8 3. get Fatal error. Actual Results: root@test:~$ modprobe -r powernow-k8 FATAL: Module powernow_k8 is in use. Expected Results: unload the module and cpuspeed and processor speed fluctionation stop. Additional info:
you can stop cpuspeed fluctuation by running 'service cpuspeed stop'
yes, but it doesn't actually stop until reboot on the AMD hardware I've tried. Continue to monitor the cpuspeed and it will fluctuate as will powerdraw.
I'll be trying FC5 on the same hardware soon, but as far as I can tell reboot or unloading the powernow module is the only way to make the cpuspeed stop making the cpu cycles and powerdraw fluctuate.
it should stop instantly when you shutdown the cpuspeed module. do you have the cpufreq_ondemand module loaded ? That's the only other thing that will adjust CPU speed.