On 20.3.2012, at 9.35, Rajesh M wrote:
i migrated my email server with around 5000 users from dovecot version 1.2 to version 2
i have two separate 2 tb hdd's storing webmail data of these users.
You mean you simply upgraded the Dovecot version, the server is exactly the same?
the load on the server goes very high over 100 during peak load times and the imap connections get dropped frequently, webmail becomes very slow.
There shouldn't be much performance difference between v1.2 and v2.x.
in the dovecot log file i get errors as such
Warning: Maildir /homebackup/domains/xxxx/xxxx/Maildir/.ALL_INBOX MAIL: Synchronization took 71 seconds (20 new msgs, 0 flag change attempts, 0 expunge attempts)
This simply means that the disk IO usage is very high.
i am a bit confused as to what settings are to be done for a very busy server
Show dovecot -n output of the new server, and if you have the old configuration available that could be helpful also to compare their differences.