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

From: Lee Revell
Date: Wed Jul 13 2005 - 00:38:53 EST


On Tue, 2005-07-12 at 15:22 -0700, Martin J. Bligh wrote:
>
> --On Tuesday, July 12, 2005 16:58:44 -0400 Lee Revell <rlrevell@xxxxxxxxxxx> wrote:
>
> > On Mon, 2005-07-11 at 21:30 -0700, Martin J. Bligh wrote:
> >> Some sort of comprimise has to be struck for now, until we get sub-HZ
> >> timers. I'd prefer 100, personally (I had that set as default in my tree
> >> for a long time). Some people would prefer 1000 or even more, maybe.
> >> 250/300 seems like a reasonable comprimise to me. Exactly what problems
> >> *does* it cause (in visible effect, not "timers are less granular").
> >> Jittery audio/video? How much worse is it?
> >
> > OK, here's a real world example, taken straight from the linux-audio-dev
> > list today.
>
> OK, what level causes Midi stuttering to stop then, under some fairly
> reasonable load? Of course ... if we set HZ to 100000, we'll get higher
> res still ... the question is how high it *needs* to be ;-)

I don't remember the details, but they can be found in the list
archives. I only remember that 100HZ is not good enough and 1000HZ is
OK.

Anyway it looks like this is a done deal. If it breaks a lot of apps
then we'll have to deal with it.

Lee

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