Description of problem: acpi_pm_read seems to eat too much CPU time according with perf top. Version-Release number of selected component (if applicable): 3.3.2-1.fc16.x86_64 How reproducible: perf top Steps to Reproduce: 1. 2. 3. Actual results: Too much CPU usage by acpi_pm_read. Expected results: Much lower usage for acpi_pm_read. Additional info: Maybe is normal, but looks too big and the machine seems a bit sluggish. Hard to say when it started. Thank you.
More info: This is where time is spent: 99.51 : ffffffff814a9850: and $0xffffff,%eax Hardware: Intel(R) Core(TM)2 Duo CPU E8400 @ 3.00GHz
acpi pm timer is slow. there's no bug here.
I can understand that is slow, but 9%?! I switched to tsc and it eats ~5%. Isn't it still too much?! I run a perf and I generated the attached file. Seems that radeon eats a lot of resources in detecting DVI output. Monitor is connected on DVI. radeon_dvi_detect appears a lot of time in the call stack. Probably should be assigned to radeon.
Created attachment 584547 [details] perf trace number 1