It seems to be when reading all the subfolders, hich was very quick in RC4.

I will do your proposal of running strace for further details

Timo Sirainen wrote:

On Jun 7, 2009, at 11:58 PM, Joan wrote:

...

Switiching to RC5, there is a visible decrease in performance to access via IMAP large accounts (>1G) with mutiple mailboxes per accounts.

In RC4, there was no delay visible by a human when accessing locally. Now it takes up to 4 or 5 secs.

When is the delay? When logging in? When opening a mailbox? When opening a message? Running strace -tt -p <imap process pid> might be interesting and show what is taking the most time.

I don't think I really changed anything big between rc4/rc5.