On 27/08/2012 5:03 PM, Timo Sirainen wrote:
On 24.8.2012, at 13.53, Tim Smith wrote:
Having set up my mail server (Dovecot/Postfix), users are experiencing long delays (a couple of minutes) when sending mail from mail client such as Thunderbird - this increases with attachments. Having had a brief discussion with someone, they mentioned that the reason that this may be to do with the size of the mailbox. I couldn't see the rationale behind this unless Dovecot is syncing the mailbox after every sent mail (due to possibly saving the sent item?) The mail is being delivered successfully but the amount of time it is taking to complete the action is far too long! Other than the bandwidth others already mentioned, the only reason it could be Dovecot's fault is exactly the size of the Sent mailbox. How large is that and what mailbox format are you using?
I missed the original message, but if your users are using Thunderbird I've seen slow sending of email be caused by a large number of temporary files being created by Thunderbird (it doesn't clean up properly), and so when it goes to create a new temporary file it goes very slowly - it may be worth checking the users mailboxes to see if they have a large number of temporary files with a similar name but different number (I forget the name, sorry - it might start with something like "nsmail", but may not).
Stop Thunderbird, clear out the temporary files, and sending becomes much faster (if this is the cause of the problem).
Regards, Michael.