Big picture...

Hal Murray hmurray at megapathdsl.net
Tue Apr 18 04:58:42 UTC 2017


gem at rellim.com said:
> But, I see no point not to do the offsets as timespec's too.  Otherwise big
> time corrections need multiple jumps due to loss of precision in the doubles
> for large 'gate' times.  And the time sve in doubles is lost in the
> converting back and forth.

[What's a "time sve"?  I can't find a typo that turns it into something 
useful.]

I think the code using doubles would be much easier to read.

If we convert from an offset in l_fp to double, we get sub ns resolution for 
small offsets.

How big an offset can a double hold with ns precision?  53 bits of ns is many 
seconds.  So anything but the first long jump will be OK.  I'm happy with 
that.

It might be in interesting experiment.  Set the time so that it is off as far 
as possible and we get the worst precision through a double.  Then start 
ntpd.  Compare that with the time starting off by 1000 seconds.


-- 
These are my opinions.  I hate spam.





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