On Tue, Oct 14, 2008 at 23:37:21 -0400, H.S. wrote: [...]
> I noticed that in FC9, the sound was working quite smoothly even when > the processor was quite busy (updating and installing stuff using yum). > This was a surprise to me. With as busy processor in Debian, I usually > get some sort an interruption in the sound. That prompted me to try out > pulseaudio in Debian too. Soon discovered it is pretty cumbersome to > install though. Keep in mind that such differences in latency can also be caused by the kernel, specifically the I/O scheduler, the timer frequency and the preemption model. It is possible that the FC9 kernels are more aggressively optimized for low-latency desktops and multimedia applications. $ grep -E 'PREEMPT|_HZ|DEFAULT_IOSCHED' /boot/config-$(uname -r) CONFIG_DEFAULT_IOSCHED="cfq" CONFIG_PREEMPT_NOTIFIERS=y CONFIG_NO_HZ=y # CONFIG_PREEMPT_NONE is not set # CONFIG_PREEMPT_VOLUNTARY is not set CONFIG_PREEMPT=y # CONFIG_PREEMPT_RCU is not set # CONFIG_HZ_100 is not set # CONFIG_HZ_250 is not set # CONFIG_HZ_300 is not set CONFIG_HZ_1000=y CONFIG_HZ=1000 CONFIG_DEBUG_PREEMPT=y In my experience, CONFIG_DEFAULT_IOSCHED="cfq", CONFIG_PREEMPT=y, and CONFIG_HZ=1000 help to decrease latency. The Debian stock kernels have CONFIG_PREEMPT_NONE=y and CONFIG_HZ=250, which is why I compile my own kernels for desktop systems. -- Regards, | http://users.icfo.es/Florian.Kulzer Florian | -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
