[ntp:questions] high precision tracking: trying to understand sudden jumps

Unruh unruh-spam at physics.ubc.ca
Mon Mar 31 16:45:47 UTC 2008

David Woolley <david at ex.djwhome.demon.co.uk.invalid> writes:

>Bill Unruh wrote:
>> On Sun, 30 Mar 2008, starlight at binnacle.cx wrote:

>You appear to be quoting an off list reply with no indication of 
>permission, although it is just possible that the email gateway 
>forwarded it to email subscribers without forwarding it to the usenet 
>group proper.

He went off list because he was banned on list for a day because of his
attempts to post graphs on line (He did not realises, as he said in his
posted post, that he could not post graphs online. He does now.) 

>Incidentally, what he's done is to run together the peers information 
>from many machines, so there is only one CDMA source.  On the other 
>hand, it doesn't look like it is a CDMA appliance, or if it is, it has 
>been badly implemented, as I would not expect to see a local clock 
>driver on an appliance device.

Ah, perhaps. Even then his list looks weird.

>The delays are rather large for the paragon of perfection of a network 
>that was described.

Yes, that was one reason I wanted to see his peerstats file as well.
loopstats has gone through the clock_filter and the selection algorithm and
gives a poor representation of what is actually on the net. But at 16sec
poll it is a pretty large file for one day. But he can graph it. 

>He probably needs to be aware that normal applications on the Windows 
>boxes will see times with a resolution that is rather poorer than can be 
>seen by ntptrace, as ntptrace takes advantage of the ntpd tick 
>interpolation, but normal applications will see times with a resolution 
>of one clock tick.

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