[ntp:questions] 64-bit serialpps.sys despite unsigned?

David J Taylor david-taylor at blueyonder.co.uk.invalid
Thu Mar 17 12:31:35 UTC 2011

> Which apparently allows ongoing, hands-off use of unsigned drivers
> after initial setup.  I am curious to hear from anyone who tries it
> with serialpps.sys and ntpd on Windows.
> Cheers,
> Dave Hart

It's certainly working, Dave, and that's great news!  Compare the plot of 
PC Alta from 07:30 UTC this morning when the 64-bit PPS was installed:


Having the kernel-mode has provided a major improvement in the "noise" on 
the offset, frequency and jitter plots.

However, it doesn't seem to be working anything like as well as nominally 
the same software installed in 32-bit Windows on PC Stamsund.  Compare the 
offsets of 32-bit PC Stamsund (well under 50 microseconds) with 64-bit PC 
Alta (well over 500 microseconds and somewhat periodic).

Looking in more detail, the offset as reported by NTP is varying from 
approximately -0.4ms to +0.4ms with a period of about 1.62 minutes (~97 
seconds).  That particular PC does have a very tight lock to another PC 
(server with max poll = 8 seconds), so I'll drop that back to 32s like the 
other servers and see if it makes any difference.  Changed at 12:30 UTC. 
I'm not expecting to see a difference, but one never knows!


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