Best practice for variables shared between processes?
alex at digriz.org.uk
Tue Sep 21 08:32:42 BST 2010
Roger Burton West <roger at firedrake.org> wrote:
> I wish to have two processes, a "producer" (which will create files) and
> a "consumer" (which will do something with them), running
> simultaneously. Ideally the producer would push filenames to a list as
> it finishes producing them, while the consumer would shift them off the
> same list (or loop-wait, if the list is empty).
I usually prefer the 'maildir'esque approach where you have a 'queue',
'processing' and 'processed' directory structure. More exotic
approaches can involve cups (yes the printer daemon) or you could get
your producer to schedule the job by priming the 'at' daemon.
With the latter two you are not dependent on the filesystem and making
sure everything is atomic...plus the job processing of at/cups is pretty
I probably would opt for 'at' (use cups if the consumer is on different
nodes, distributed?) as conceptually you do not then need to put queuing
functionality and logic into your scripts and it is dead easy to
rescheule a job.
.sigmonster says: This system will self-destruct in five minutes.
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