✘sys_fuzz * ntp_random()

[Achim Gratz]

Gary E. Miller writes:
> Dr. Mills did not put it there.  This was added in 2011 by Dave hart.
> See my previous email that probably crossed by yours in flight.

The way I read things, Dave Hart's patches were to ascertain
monotonicity on top of the already existing fuzzing.

> It proves that sys_fuzz does nothing on a RasPi.  At least undetectable
> over 4 days.  I give you it proves nothing about other systems.

The fuzz we are talking about is added to outgoing timestamps, so when
it did something it wouldn't be discernible on the server, but on the
client receiving that timestamp.  In other words, you are looking at the
wrong end of the data (I think).

> I'll once again raise the challenge to someone else to prove it
> actually does something, somewhere.  No point involving deities or
> more bike shedding, give me data!

You can make such requests ad inifinitum, but it won't help.  Unless you
know what exactly the problem was that fuzzing solves, you won't be able
to pick out that set of data that shows you whether it is or is not
still needed.

> Now knowing more about bug 2037 I'm also confident that the
> characteristics of the RasPi clock where not those being fixed in bug
> 2037.

That bug was about monotonicity of the timestamps, not the fuzzig
itself, IIRC.

Again, you need to know what problem this code was solving (before the
patches from Dave Hart, which were solving a different and probably more
specific problem most likely) in order to know if the assumptions that
made it necessary or useful still hold.


Regards,
Achim.
-- 
+<[Q+ Matrix-12 WAVE#46+305 Neuron microQkb Andromeda XTk Blofeld]>+

Wavetables for the Waldorf Blofeld:
http://Synth.Stromeko.net/Downloads.html#BlofeldUserWavetables