Hello,

I'm migrating a mail server from a centos 5 cluster architecture to a centos 6 cluster architecture. The new cluster involves faster machines then the old cluster, and a virtual machine. I use dovecot-2.0.9-5.el6.x86_64, while the old cluster uses dovecot-2.0.1-1_118.el5. Tha mail server uses mysql for the users database, and a local ldap for authentication.

The storage is also much faster in the new cluster: OLD SERVER: date; dd if=/dev/zero of=/cl/prova.bin bs=102400 count=10240; sync; date Wed Jun 26 15:43:53 CEST 2013 10240+0 records in 10240+0 records out 1048576000 bytes (1.0 GB) copied, 30.0202 seconds, 34.9 MB/s Wed Jun 26 15:44:28 CEST 2013 --> 1GB / 35 secs = about 29.25 MB/sec

NEW SERVER: date; dd if=/dev/zero of=/cl/prova.bin bs=102400 count=102400; sync; date mar 25 giu 2013, 15.46.36, CEST 102400+0 records in 102400+0 records out 10485760000 bytes (10 GB) copied, 62,5143 s, 168 MB/s mar 25 giu 2013, 15.48.33, CEST [root@eta ~]# ---> 10GB / 117secs = about 85.47MB/sec

An 'ls -l' in the user direcotry is also much faster, when the ldap/sssd cache is populated:

OLD SERVER: real 0m8.540s user 0m1.229s sys 0m0.699s

NEW SERER: real 0m3.938s user 0m0.250s sys 0m0.151s But my imaptest is much slower:

./imaptest user=XXXXXXX pass=XXXXXXX secs=120 seed=123 mbox=./dovecot-crlf OLD SERVER:

Totals: Logi List Stat Sele Fetc Fet2 Stor Dele Expu Appe Logo 100% 50% 50% 100% 100% 100% 50% 100% 100% 100% 100% 30% 5% 1122 559 547 1121 1121 1568 136 900 1121 1121 2244 NEW SERVER Totals: Logi List Stat Sele Fetc Fet2 Stor Dele Expu Appe Logo 100% 50% 50% 100% 100% 100% 50% 100% 100% 100% 100% 30% 5% 390 210 185 389 389 589 49 320 389 389 780

The configuration is exactly the same in the 2 clusters, that is:

# 2.0.1: /etc/dovecot/dovecot.conf # OS: Linux 2.6.18-348.3.1.el5 x86_64 Red Hat Enterprise Linux Server release 5.9 (Tikanga) xfs auth_cache_size = 1024 auth_cache_ttl = 21600 s auth_debug = yes auth_debug_passwords = yes auth_master_user_separator = * auth_mechanisms = plain login auth_socket_path = /var/run/dovecot/auth-userdb auth_verbose = yes base_dir = /var/run/dovecot/ disable_plaintext_auth = no hostname = mail.unimore.it info_log_path = /var/log/dovecot.log lda_mailbox_autocreate = yes log_path = /var/log/dovecot.log mail_debug = yes mail_location = maildir:/cl/mail/vhosts/sms.unimo.it/%Ln/Maildir mail_plugins = $mail_plugins quota mailbox_idle_check_interval = 60 s mbox_write_locks = fcntl namespace { inbox = yes location = prefix = INBOX. separator = . type = private } passdb { args = /usr/local/etc/dovecot.masterusers driver = passwd-file master = yes } passdb { args = dovecot driver = pam } plugin { quota = maildir:User quota quota_exceeded_message = Quota exceeded (mailbox is full) quota_rule = *:storage=200MB quota_rule2 = *:messages=100000 quota_rule3 = INBOX.Trash:storage=+100M quota_warning = storage=90%% quota-warning 90 %u quota_warning2 = storage=85%% quota-warning 85 %u quota_warning3 = messages=95%% quota-warning 95 %u quota_warning4 = messages=80%% quota-warning 80 %u setting_name = quota } postmaster_address = postmaster@unimore.it quota_full_tempfail = yes service anvil { client_limit = 199999 process_limit = 1 } service auth { client_limit = 21224 unix_listener auth-userdb { mode = 0600 user = vmail } } service imap-login { inet_listener imap { port = 143 } inet_listener imaps { port = 993 } process_limit = 10000 } service imap { process_limit = 10000 } service pop3-login { inet_listener pop3 { port = 110 } inet_listener pop3s { port = 995 } } service pop3 { process_limit = 1024 } service quota-warning { executable = script /usr/local/bin/quota-warning.sh unix_listener quota-warning { group = vmail user = vmail } user = dovecot } ssl_ca =

Is anyone able to tell me what I have to check?

thanks in advance

Fabio Ferrari