Arnold de Leon <arnold@Synopsys.COM> writes:
# I don't believe ordering of near simultaneous commands to
# majordomo is important.
I was actually thinking of ordering of postings via "resend", which
can be somewhat important to preserving the semantic thread of a
conversation. I agree that ordering of commands isn't important.
In looking at it a little, it appears that "resend" doesn't use the
locking open anyway; nor can I think of any reason why it should. So,
just ignore what I said yesterday; it don't make no sense... Chalk it
up to staying up too late at Interop.
# I am planning to write a "abort, retry"
# routine for majordomo (basically cleanup and exit EX_TEMPFAIL).
# so I that several failures can be retried
# Then I can have the lock failures optionally fail with
# "abort, retry". This would prevent too many processes from
# waiting for locks and taking up swap space.
#
# This has the advantage of using the queueing mechanism
# implemented by the mail system already.
Do mailers other than sendmail pay attention to EX_TEMPFAIL?
# Some observations and other data:
#
# o it takes aprox 20 seconds to process an {un}subscribe
# command on 3500+ address mailing list
#
# o The time to process an {un}subscribe command
# grows linearly with the size of the list.
#
# o the machine I use is a Solbourne S4000DX (aprox. a
# Sparcation 2 class machine)
#
# o multiple majordomo processes using spin locks
# causes enough trashing that a given subscribe
# call would timeout if several subscribe
# requests came in as separate messages.
#
# o The backoff that I implemented stops backing
# off at 60 seconds.
#
# o The first few retries will occur 1, 2 and 4 seconds
# later. This behaviour is similar to the spin locks
# in terms of responsives.
#
# o I believe that if the lock was not available after
# ~8 seconds then the resource is probably going to be
# unavailable for a while.
#
# o I have been running with the backoff code for over
# 6 weeks. It's definitely better than the old way.
Cool; it's clear that you've done a lot more work on this than I have,
and I was somewhat confused anyway, so never mind my earlier comments.
I _still_ want someone to implement (or point me to) a general queue
package in Perl, though... :-)
-Brent
--
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