[ntp:questions] 500ppm - is it too small?

Dave Hart davehart at gmail.com
Fri May 8 04:47:21 UTC 2009

I believe the 500 PPM limit is inherent in the Unix adjtime interface
ntpd uses to slew the time, though it may well have been chosen based
on NTP's design limit.  For what it's worth, the Windows time-slewing
interface has no PPM limit.  If the daemon clock discipline loop code
so chose, ntpd on Windows could slew at a greater rate than 500 PPM.

Dave Hart

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