[coyotos-dev] coyotos.sleep, sleepTill, the epoch

[Sam Mason]

On Mon, Feb 12, 2007 at 12:15:46AM +0100, Valerio Bellizzomi wrote:
> >> Something you definitely do NOT want is a 1ms granularity interrupt to
> >> maintain a tick counter. On current hardware this will account for a
> >> measurable fraction of the machine.
> >
> >Yes, I was very surprised when Linux got this!
> 
> The hardware clock on a PC uses a low cost time base oscillator. It is
> imprecise in any case.

I think the main reason it was done under Linux was for scheduler
improvements rather than increased timer/clock accuracy.

> So why don't just grab the BIOS time-of-day when we need it?

I think because you need to know the time surprisingly regularly, also
as far as I can tell it will only give you the time to the nearest
second anyway.  This is reasonable, but doesn't help the scheduler much.


  Sam