Re: PSA: Clock drift and pkgin

 

On Sunday, December 24, 2023 at 02:43:55 AM PST, Johnny Billquist <[email protected]> wrote:

> Oh? So we are actually not POSIX compliant on that one? Interesting.
> (POSIX explicitly says that the timeout should be for an absolute time,
> which means that if you for example update the clock, moving it
> backwards, the timeout should still only happen when that time arrives,
> and not after some precomputed number of ticks.)

one could keep track, for every timeout, whether it's relative or absolute;
and when the time is changed, walk the list of a-yet-unfired timeouts,
updating all the "absolute" timeouts by the clock-change delta.

Anyway .. I wonder if the "clock drift" is related to the clock drift I've heard about,
on machines which don't have a hardware cycle-counter-style clock, and rely on clock-tick
interrupts to track time. (for example, pmax 2100/3100; decstation 5000/200; (most) vax).

I'd really like to help out with clock-drift', if I can do anything to help.