On Mon, 2010-01-25 at 13:16 +0000, Andrew Hearn wrote:
dovecot: Warning: chdir(/maildir/x.co.uk/users/y) blocked for 18 secs This tends to last a minute or so for different users.
/maildir is a NFS mount, and I'm suspecting it's the NFS server being busy and dovecot having to wait.
Right.
Other than replacing the NFS server with faster hardware is there anything else we can do?
Nope. Although with v2.0 the warning is gone, it'll just silently wait for however long it needs to. But then it's the imap/pop3 process that waits, not a forked "dovecot" master process, which was causing confusion.
Oh, and of course you could try to reduce disk I/O on the NFS server. If you've only a single Dovecot server, you can keep using mail_nfs_storage=no. Also you could try maildir_very_dirty_syncs=yes if you've nothing else besides Dovecot touching your maildirs.