Sound Jitter.

Roland Smith rsmith at
Tue Jun 21 17:37:42 GMT 2005

On Mon, Jun 20, 2005 at 11:21:15PM +0100, Grant wrote:
> > Try enlarging the soundcards DMA buffer; Add the following line to
> > /boot/device.hints and reboot:
> > 
> > hint.pcm.0.buffersize="16384"

> I found the above line on google when i had a looke, i shoved it in but
> with another number 65536 i dont know if that made a difference, but i
> tried the exact line above with that number.
> The Jitter is still there, but instead of happening when firefox is
> scrolling its only when firefox is just about to finish loading
> something, which i suppose would cause a CPU spike or something ? also
> during playback firefox runs very very slow :/ i dontk now if this is
> related at all, but with the cpu and the ram it shouldnt run that bad,
> the window manager is fluxbox so thats keeping things to a minimum.

Some things you might try (might be totally off-base :):

- run the player at a higher priority (with nice(1)).
- have the scheduler make smaller slices; set the kern.sched.quantum
  sysctl to a smaller value.

I thought there was another sysctrl for the ratio of user process time
to system time, but I can't remember.

R.F.Smith ( Please send e-mail as plain text.
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