[ntp:questions] What level of timesynch error is typical on Win XP?

Evandro Menezes evandro at mailinator.com
Fri Oct 22 14:11:25 UTC 2010


On Oct 21, 10:00 am, "David J Taylor" <david-
tay... at blueyonder.co.uk.invalid> wrote:
> Windows can run NTP at real-time priority, if you give the NTP user that
> right.  Normal user processes will not then pre-empt NTP.

Yes, except that Windows ends up raising the effective priority of
system tasks that supersede NTP's effective priority.  Among the worst
offenders, network DPCs and some disk DPCs with some anti-virus
programs (i.e., Mcafee).

Then, even tasks with real-time priority will and do get starved and
an algorithm like NTP's, which has hard deadlines, suffers, thus the
inherently higher jitter in Windows.




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