performance issue (imap spool on san)

Michael Loftis mloftis at
Wed Jul 26 12:06:28 EDT 2006

--On July 26, 2006 12:02:41 PM +0200 Rudy Gevaert <Rudy.Gevaert at> 

> Hi,
> I've installed the latest cyrus release and I'm having trouble with large
> mailboxes.
> I was going to try if the 4Gig limit is gone and I'm filling up a mailbox
> with mails.
> If I open the mailbox trough mutt it gets loaded at a acceptable
> (lighting fast) speed.  However when using thunderbird it gets very slow,
> I haven't been able to open the mailbox of 294M.

This is a thunderbird problem, not a Cyrus problem.  Thunderbird is NOT an 
IMAP client.  It's a POP3/NNTP reader, that's been taught to badly parrot 
IMAP.  It attempts to download and locally index *all* headers.  This means 
that for large mail stores, it'll take a LONG time to figure out whats 
going on, and lots and lots of RAM too.  And this is all on the Client.


> The above logs are only an extract of the output.  These messages are
> going in slow bursts.
> The imap spool and configdirectory are on a SAN.  How can I further debug
> this?

Your SAN is fine, your client is the problem.  Unfortunately since Cyrusoft 
went under (they made Mulberry) aside from Mutt and Pine I don't really 
have any suggestions for loading large mailboxes.

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