Martin Burnicki wrote: > Here, 2 consequent QPC calls retrun a difference of ... > 350..400 ns using TSCs on an Intel 3 GHz CPU
That's horrible! Since the RDTSC takes less than 10 ns on that cpu, the remaining 340-390 ns is lost in the OS library interface. :-( > 1.6..1.9 us using the PM timer on my AMD x64 4400+ > > I think the difference is not relevant for NTP. 2 us vs 10 ns _can_ be significant, but only if we have at least 10k timing calls/second. Terje > -- - <Terje.Mathisen at tmsw.no> "almost all programming can be viewed as an exercise in caching" _______________________________________________ questions mailing list questions@lists.ntp.org https://lists.ntp.org/mailman/listinfo/questions
