Subject: [Exim] What to do about non-monitonic process ids
> Folks, I need some feedback.
>
> http://cus.cam.ac.uk/~ph10/exim-pid-message
>
> Feedback is invited. I guess it's best on the list so everybody can
see
> the discussion (if one ensues).
>
> Philip
>
> --
> Philip Hazel University of Cambridge Computing Service,
> ph10@??? Cambridge, England. Phone: +44 1223 334714.
>
I support the following idea, taken from Philip's posted discussion:
>IDEA 3: USE THOSE HYPHENS
>-------------------------
>
>In this scenario we abolish the hyphens in the ID, and make it up to
>16-characters by extending the time field with another two base-62
>digits, which can hold milliseconds. This is entirely compatible and
>doesn't eat into the PID field, but it makes the IDs less readable.
>You'd have things like this:
>
> 18e2IE450006eL00
>
>What do people think?
What I think is, the ID's are not human-readable anyway (at least, not
to THIS human!). Whenever I want to do something with one, I never type
it by hand, but use whatever "cut & paste" feature is available. Go
ahead and make maximum use of the 16 characters you have, without
suffering the "major upheaval" problem.
Another possibility is to move up to a larger base system. Yes, I
understand you'd have to be careful not to use things that have
"special" meaning to many script languages, and so forth. But even just
a few extra characters could add significantly to the number of bytes of
information that could be stored in 16 characters. Number of unique
values = (base number) raised to the (number of characters).
Thus, a 16 character base-62 can store up to
47672401706823533450263330816 unique values. Increasing to base 66 (say
by adding extra characters _-+=) takes us to
129629238163050258624287932416 unique values (a factor of almost 2.72
increase).
(Aren't computers wonderful? Imagine doing those calculations with
pencil and paper! Darn. Just dated myself again, didn't I? Can you
say "Heathkit 4-Banger"? *ducks back into cave*)
Jim Roberts
Punster Productions, Inc.
