Re: [PATCH] i386: Selectable Frequency of the Timer Interrupt

Lee Revell
2005-07-12T14:28:44Z

On Mon, 2005-07-11 at 21:30 -0700, Martin J. Bligh wrote:
> Exactly what problems
> *does* it cause (in visible effect, not "timers are less granular").
> Jittery audio/video? How much worse is it?

Yes, exactly. Say you need to deliver a frame of audio or video every
5ms. You have a rendering thread and a display thread that communicate
via FIFOs. The main thread waits in select() for the next frame to
complete rendering or for the deadline to expire. That's next to
impossible with HZ=100, because the best you can do is the deadline
+-10ms. With HZ=1000 it's no problem.

Lee