[ntp:questions] Re: clock resolutions for different OS

David L. Mills mills at udel.edu
Thu Aug 21 16:39:22 UTC 2003


Not true. If the kernel has routines consistent with nanosecond
resolution, both the library and PPS driver use nanosecond structures
and computations.


Piotr Trojanek wrote:
> In article <bhvd3a$b6i$1 at dungeon.mctavish.co.uk>, Steve Woodford wrote:
> >Partially correct. On x86 CPUs, NetBSD-1.6.x, and earlier releases, use
> >the traditional timer-based microtime(). NetBSD-current on x86 uses the
> >cpu cycle counter, if available (and known to be trustworthy).
> I don't know much about -current, but checked it -- the PPS and NTP
> routines use cycle counter, but still keeps timestamp in 'struct timeval',
> which has only 'usec' resolution.
> --
> Piotr Trojanek

More information about the questions mailing list