On Sunday, October 24, 2010 11:18:45 pm Arjan van de Ven wrote: > On 10/24/2010 8:39 PM, Gabriel M. Beddingfield wrote: > > Hello, > > > > When doing processor intesive calculations (e.g. > > synthesizing audio) I've found that the kernel option > > CONFIG_X86_ACPI_CPUFREQ causes a big performance drop > > when it's enabled. > > > > Any ideas why this is? > > is your calculation running "nice"? because if so, you > may get less CPU frequency than the maximum > (which is all you'll get without that CPUFREQ).
OK. That pretty much answers it. See details below. Anybody know how to configure the speed profile (swich from "on demand" to "performance"?) > your bug report is rather vague.... can you be more > detailed on which meego you are using, > give us "powertop -d" output while your intensive > calculation is running... and information > on what kind of hardware this is. When I say "processor intensive" -- I mislead you. I'm intermittently calculating audio. Whenever it's time to calculate -- it's intensive and I need a fast response. When not calculating audio, the application is idle. I.e. every 5 ms I need to calculate 5 ms of audio. In this case, 5 ms of audio is perhaps 3000-6000 flops. Thus, since I'm not keeping the CPU pegged the power manager isn't keeping the speed high. powertop -d gives (among other things).... P-states (frequencies) 1.67 Ghz 16.2% 1333 Mhz 3.3% 1000 Mhz 80.6% Top causes for wakeups: 71.0% (1570.5) [kernel scheduler] Load balancing tick 15.6% (344.9) [hda_intel] <interrupt> 7.4% (162.5) energyXT 3.7% ( 82.3) [Rescheduling interrupts] <kernel IPI> 0.2% ( 5.0) jackdbus -gabriel _______________________________________________ MeeGo-dev mailing list [email protected] http://lists.meego.com/listinfo/meego-dev
