Re: [Bloat] Steam In Home Streaming on ath9k wifi

[Hal Murray <hmurray@megapathdsl.net>]

neil.davies@pnsol.com said:
> There are a few more issues - the relative drift between the two clocks
> can be as high as 200ppm, though typically 50-75ppm is what we observe, but
> this drift is monotonic.

200 ppm seems pretty high, but not off scale.  If ntpd is running and not 
getting confused by long queuing delays, it should correct the drift to well 
under 1 ppm.  If you turn on loopstats, you can graph it.

If you are blasting the network and adding long queuing delays, ntpd can 
easily get confused.

There is another quirk to keep in mind.  The temperature coefficient of the 
crystal is ballpark of 1 ppm per C.  Things can change significantly if an 
idle system starts flinging lots of bits around.


> Also NTP can make changes at one (or both) ends - they show up as distinct
> direction changes in the drift. 

I'm not sure what you mean by "direction change".  I'd expect a graph of the 
time offset vs time to be linear and the slope would have a sharp change if 
ntpd changed it's "drift" correction and/or maybe a rounded bend as a system 
warmed up.

----------

Are you happy with whatever you are doing?   Should we try to set things up 
so ntpd works well enough?  How close would you like the times to be?  ...




-- 
These are my opinions.  I hate spam.