[ntp:questions] Clock and Network Simulator

Rob nomail at example.com
Fri Jul 2 07:09:17 UTC 2010

David L. Mills <mills at udel.edu> wrote:
> Rob,
> Your comment makes no sense. The actual code implemented from my design 
> was tested in Solaris and also in FreeBSD. In both cases the tests 
> confirmed the behavior described previously. I have not tested it in 
> Linux. If it performs other than as I described, the port is broken.
> Dave

Unbelievable that you still write this when after a lot of denial you
had to admit on June 15th that there actually was a bug in code that
was in ntpd for many years:

 The contraption was working correctly, but the tally code was incorrect
 when the reach register was zero. I chased this down and found a most
 bizarre cause. The problem occurs when there are no selectable samples
 in the clock filter when the last bit is shifted out of the reach
 register. In your tests and mine there have been at least two selectable
 samples in the clock filter; but, depending on the sort order, there
 could be one or none. I fixed the problem in the development version.

 I would like to emphasize two points. First, the problem extended only
 the the tally indicator and the program was otherwise working correctly.
 Second, the contributions of others not on the bugs list was vital for
 the solution. And, in fact, this particular hazard has existed since 1992.

You may be the perfect programmer, no doubt, but there always could be
bugs in the code that earlier testing has not revealed, no matter on what
platform it was performed.

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