Martin Burnicki wrote: [] > This points to the problems with Windows time if a multimedia > application is started. I've mentioned this sometimes before here in > the newsgroup, e.g. here: > http://lists.ntp.isc.org/pipermail/questions/2005-September/006709.html > > This problem is NOT from the MM apps themselves but from the way > Windows is keeping time, and AFAIK has been fixed by MS in SP2 for > WinXP. > > So you won't fix the problem by using another version of ntpd. Either > you must make sure no MM app runs at all (maybe even not in the > background, if QT looks if updates are available), or you must have > at least one MM app running continuously in order to have the MM > timer set constantly set either to highest resolution or default > resolution, but not switching between the 2 resolutions. > > If the MM timer is set constantly to high resolution then you should > observe a little more jitter than with default resolution, but the > large steps should go away. So as a test you just might to start > Quicktime ant watch if the offset settles down. > > > Martin
I've had a QuickTime video playing but paused now for the last two hours or so, It's a bit early to say yet, but it looks as if a number of things have happened: - the drift value is changing from -65 downwards, currently -59.385 - the offset has shot up to 120ms, but seems to be stable at that value (I guess if it goes up much more a step will happen at 128ms). - the jitter figures seem much better, around 2 - 3ms. Of course, that's with a high offset value so not strictly comparable. However, it does perhaps suggest that: - the poor performance before was from the time switching into and out of MM mode. - having a permanently "on" MM mode may help this system, and may be a useful feature for NTP on some Windows systems. I still have no idea what piece of software started enabling the MM-timer mode last Friday, though! I should keep better records. I'll report again tomorrow. David _______________________________________________ questions mailing list [email protected] https://lists.ntp.isc.org/mailman/listinfo/questions
