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Re: zmailer & SQL Databases
On Thu, 22 Jul 1999, Karl Pitrich wrote:
> i think it will also be a performance increase using a DB instead of
> because no locking is needed, the database has chaching, and
> any number of deliveries can happen concurently, because the db manages
> the accesses.
But it does all that by using locks. When's the last time you got an
unresolvable deadlock error trying to read your mail from
> btw, the usage will be a smaller xoom.com or hotmail like system.
I think, if you're looking for performance and scalability, you're better
off improving message access time by evolving the file system utilization.
The current unix-style mailboxes and /var/spool/mail schemes date back to
System7, when 100 users on a system was alot. You could do the following:
- hash mailboxes into numerous directories (just like the scheduler does)
- store individual mail messages in individual files in a directory (which
is the "mailbox folder", rather than stacking them into one unix-style
^From_ seperated file. This can yield a very significant improvement in
performance for deletes, addition of new messages, and changing message
headers (like changing the Status: header line), through simplfying those
tasks and eliminating alot of file contention (and lock contention).