When the platform clock is changed from the performance counter (freq: 3.554 MHz) to the HPET (freq: 14.318 MHz) the NTP protocol precision declines from -22 to -20. This occurs both in versions [email protected] May 09 10:14:35.18 and [email protected] Aug 28 12:01:29.42. The NTPD_USE_INTERP_DANGEROUS=1 environment variable is set. Here are the relevant messages from the Event Log:
8/23/2014 3:34:59 PM ntpd [email protected] May 09 10:14:35.18 (UTC-04:00) 2014 (1): Starting 8/23/2014 3:34:59 PM Command line: G:\Program Files (x86)\NTP\bin\ntpd.exe -U 3 -M -g -c G:\NTP_Conf\ntp.conf 8/23/2014 3:34:59 PM Raised to realtime priority class 8/23/2014 3:34:59 PM Clock interrupt period 15.625 msec (startup slew -0.7 usec/period) 8/23/2014 3:34:59 PM Performance counter frequency 3.554 MHz 8/23/2014 3:34:59 PM proto: precision = 0.200 usec (-22) 8/23/2014 3:34:59 PM proto: fuzz beneath 0.100 usec 8/23/2014 3:52:37 PM ntpd [email protected] May 09 10:14:35.18 (UTC-04:00) 2014 (1): Starting 8/23/2014 3:52:37 PM Command line: G:\Program Files (x86)\NTP\bin\ntpd.exe -U 3 -M -g -c G:\NTP_Conf\ntp.conf 8/23/2014 3:52:37 PM Raised to realtime priority class 8/23/2014 3:52:37 PM Clock interrupt period 15.625 msec 8/23/2014 3:52:37 PM Performance counter frequency 14.318 MHz 8/23/2014 3:52:38 PM proto: precision = 0.800 usec (-20) → → No "proto: fuzz beneath ... " message ← ← 9/4/2014 5:57:34 AM ntpd [email protected] Aug 28 12:01:29.42 (UTC+01:00) 2014 (1): Starting Repeats exact same sequence as on 8/23/2014 3:52:37 PM Is this the way it should be, that the protocol precision declines when the clock is more than 4 times faster? Charles Elliott _______________________________________________ questions mailing list [email protected] http://lists.ntp.org/listinfo/questions
