[ntp:questions] Re: ntpd transmit timestamp precision

Damion de Soto damion at cyberguard.com.au
Tue Feb 14 01:43:37 UTC 2006

Brian Utterback wrote:
> Yes and no. If your system supports either clock_gettime or getclock,
> then the code does not bother with the random bitstring, since there
> are only two unused bits to set. Not worth the trouble.

Thanks, but I have a system here that has very low resolution system clock,
ntpd correctly detects this via default_get_precision() as:
Feb 13 07:01:31 ntpd[59]: precision = 10000.000 usec

I have clock_gettime() available to me, but the nanoseconds values will be mostly 
wrong, since 10ms only gives me 7 bits of precision.
This means all 64bits of the fractional seconds in the Transmit Timestamp are nearly 
always the same.

Has no-one else ever run into this before?


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