Re: scheduler wish list

[Andy Poling <andy@jhunix.hcf.jhu.edu>]

On Tue, 27 Jul 1993, Matti Aarnio wrote:
> > The is scheduler's inability to maintain state from one instance to
> > another. If scheduler dies or the machine dies or is down for some reason,
> > all sense of message age disappears.  It would be super useful if
> > scheduler kept a record of the state of the messages on disk so that it
> > could pick up where it left off.  Naturally, this is a greater problem for
> > sites like us who are pushing the envelope (in numerous directions :-) but
> > it seems like a necessary feature given ZMAILER's stated design goals.  It
> > even already knows how to dump its state (hint - MAILQ and rendezvous
> > file) - all that remains is a method of reading it back and making use of
> > it. 
> 
>   Message age is never lost, however scheduler seem to have several
> holes in it, but I haven't been able to put my finger on any specifics.
> Message age is taken from the original message file  st_ctime, thus
> as it is never modified, message age is known.

Rayan also said in private mail that age/expiry time should be
retained.  When I tried shutting down the scheduler and starting a new one
just now, it appears that that was the case.  I swear, though, that that
has not been the case when the machine has crashed (or the scheduler has
crashed - it happens occasionally).  I can't explain it...

Regardless, ZMAILER is the best mail system I've ever run.

-Andy

Andy Poling                              Internet: andy@jhunix.hcf.jhu.edu
UNIX Systems Programmer                  Bitnet: ANDY@JHUNIX
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