[Dovecot] Dovecot very slow on a mailbox with > 700 IMAP Folders

[Timo Sirainen]

On 5.5.2011, at 10.19, Timo Sirainen wrote:

>> I did some debugging with strace, too. It's about 22MB only for running the lsub command !?
> 
> Run it with strace -tt and send me the output compressed?

Ah, you have ACLs enabled. With ACLs it's looking up dovecot-acl file from each folder before returning it. This shouldn't be necessary with LSUB I think. I suppose some kind of an ACL cache could be a good idea some day too. And maybe a setting not to bother looking up ACLs for mailboxes in private namespaces.

I'll try to do something about those within a few days..