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SubjectRe: PC speaker driver patch for 2.4.0-test10-pre3
Hi!

> > oxymoron@waste.org said:
> > > You can also pretty trivially keep track of an error term so that the
> > > clock is right on average:
> >
> > True, but I don't want 'right on average'. I want 'not screwed with at all'.
> > Shifting the timer tick onto the RTC will give me that.
> >
> > Even if we _do_ get the maths right, fudging with the frequency of the
> > system timer is still an ugly hack.
>
> I personally think the system timer is already an ugly hack. HZ is
> arbitrary, slow by modern standards, and introduces latency.
> As the comment you quoted points out, it's also not very accurate.
> Much better would be an agenda structure with one shot timers between
> events and jiffies based on cycle counters. This works on modern hardware
> and scales well for higher processor speeds.

...and breaks horribly when your CPU frequency changes... like on most
current notebooks.
Pavel
--
I'm pavel@ucw.cz. "In my country we have almost anarchy and I don't care."
Panos Katsaloulis describing me w.r.t. patents at discuss@linmodems.org
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