Pivoting

[Gary E. Miller]

Yo Hal!

On Tue, 25 Apr 2017 17:22:28 -0700
Hal Murray <hmurray at megapathdsl.net> wrote:

> devel at ntpsec.org said:
> > Prove it.  I have already sent you a detailed analysis, you keep
> > saying no, but refuse to defend your point.  
> 
> > I can accept an "I don't know yet", but if you keep saying it is
> > wrong I expect you to be able to prove your point.   
> 
> I didn't follow your detailed analysis carefully, but I don't
> remember the key point.

Rather than repeating myself:

https://lists.ntpsec.org/pipermail/devel/2017-April/004179.html

https://lists.ntpsec.org/pipermail/devel/2017-April/004266.html

> If there is no pivot in step_clock, where is it done?

We are not talking about step_clock(), so that prolly adds to the
confusion.  We are talking about adj_systime().  That function
never change the time more than --panicgate, which is almost always
+/- 1,000 seconds.

There is one odd patch, mode_ntpdate, that never calls setp_system()
for steps more than 128 ms.

> It all works if the system time is "close enough".

Yes, and adj_systime() is only called when system time is "close
enough".  

If the step is more than panicgate (usually 1,000 seconds), then
step_systime() or adj_systime() is called.

Both those are also a mess, but one (two?) messes at a time.

> Were you assuming that? I was.

I'm not assuming that, i know the code says that.

>  Eric isn't.

I'll let Eric speak for Eric.

Given that the adjustment path is so tortured, I like the suggestion
someone made a while back to add a trace mode to the loopfilter code.

RGDS
GARY
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Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703
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