[imp] IMP 3.2.1 very slow

[Michael M Slusarz]

Quoting Andreas Danzer <ad at ixx.com>:

| lkd> Not really. I have tried Horde 2.2.3 with IMP 3.2.1 today. It is
| approx two
| lkd> times slower then horde 2.1 with IMP 3.1 on the same machine with
| same backend
| lkd> IMAP/MySQL.
|
| The same here. IMP get's extremly slow when accessing some "bigger"
| mail accounts - even with the mcrypt module activated in php.
| The performance is very disappointing - looks like we'll have to
| switch back to twiggy. :-(

This has nothing to do with 'mcrypt' or the changes made in Horde.  Instead,
it sounds like you have large mail folders.  If using either mbox format of
maildir format, past a certain size of mailbox (depending on OS, caching,
file system, software, speed of hardware, etc.) they all begin to take
performance hits on the _mail server_ side, not Horde/IMP.  For proof of
this, try logging directly into your IMAP server (e.g. 'telnet localhost
imap').  Go to a directory with a lot of messages (my trash directory has
4000+ messages in maildir format on a reiserfs file system). Then do an
IMAP search query for unread messages.

It took, on my AMD k-6 350 linux machine, about 31 seconds to perform this
query on my Trash folder.  I did the exact same query in IMP 3.2.1
(essentially, opening my Trash folder) and it took approx. 33 seconds.  So
Horde/IMP is taking about 2 seconds and the IMAP server is taking 31
seconds.  Where is the holdup?

Conclusions:
1) buy better hardware
2) don't have mailfolders larger than, say, 1000 messages
3) experiment with different mail storage options
4) don't blame IMP/Horde for _all_ performance problems

michael

______________________________________________
Michael Slusarz [slusarz at bigworm.colorado.edu]
The University of Colorado at Boulder