Intermittent failures with duplicate suppression?

[Rob Siemborski]

On Tue, 6 Apr 2004, Michael Sims wrote:

> Sorry to followup to my own post, but I have an additional question to
> whoever may have the answer.  Does Cyrus exclusively lock the deliver
> database on each delivery (when using skiplist)?  In other words, if two
> messages with the same Message-ID come in nearly simultaneously (as close to
> simultaneous as possible), is it possible for them to slip through the
> duplicate check, or will the second message be forced to wait until the
> first one has updated the delivery database before it can query it?\

Yes, there is a race here.  I think otherwise we'd be holding locks on the
duplicate delivery database for some amount of time (in order to assure
that no mail is lost because it is marked, but not delivered -- in the
event of a crash).

-Rob

-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Rob Siemborski * Andrew Systems Group * Cyert Hall 207 * 412-268-7456
Research Systems Programmer * /usr/contributed Gatekeeper

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