On Sun, 2006-07-02 at 22:20 -0400, [email protected] wrote:
> On Sun, 02 Jul 2006 18:56:22 PDT, Daniel Walker said:
> > I was reviewing these new ntp adjustment functions, and it seems like it
> > would be a lot easier to just switch to a better clocksource. These new
> > functions seems to compensate for a clock that has a high rating but is
> > actually quite poor..
> It is indeed poor - a few -mm's ago I tripped over a bug that kept it from
> recognizing the PM timer clocksource, and it refused to NTP sync because
> the clock drift was well outside the 500 ppm that NTP wants. All the same,
> it's *one* thing for a clock to be drifting 10 seconds per hour. It's
> something else to totally explode when handed a drifting clock.
Yes, the TSC is a very poor clocksource. Although its high resolution
and very quick access time makes it hard to quit.
> Currently, the kernel is build with CONFIG_RTC=m, and the clock starts
> behaving as soom as rc.sysinit modprobes it. Questions this raises:
> 1) What's up with *that*?
Hmmm. Thats an interesting observation. Let me look to see if maybe
something is going oddly in the settimeofday() path.
> 2) Anybody want to place bets that building with CONFIG_RTC=y will make
> the clock work right off the bat?
No bets here, but please let us know if you see any change in behavior.
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