Hi,

we are facing some weird performance issues after we upgraded on of our mail servers to a new Opteron 64bit machine.

The problem we are facing is that mail retrieval from external clients is incredibly slow. Fetching a mail with say a size of 3MB takes 7 minutes vs. sending exactly the same mail back to our postmaster account is only a question of seconds.

I've verified this with various customers and thus I am completely lost here. The only service affected with this massive slowdown seems to be dovecot but unfortunately I cannot think of a way to debug the issue ...

System load is absolutely minimal.

% dovecot -n # 1.0.5: /etc/dovecot/dovecot.conf log_path: /var/log/dovecot.log protocols: imaps imap pop3 listen: 81.16.98.99 ssl_listen(default): 81.16.98.99 ssl_listen(imap): 81.16.98.99 ssl_listen(pop3): ssl_cert_file: /usr/bestsolution/ssl/certs/mail.bestsolution.at.pem ssl_key_file: /usr/bestsolution/ssl/private/mail.bestsolution.at.pem ssl_parameters_regenerate: 24 disable_plaintext_auth: yes login_dir: /var/run/dovecot/login login_executable(default): /usr/lib/dovecot/imap-login login_executable(imap): /usr/lib/dovecot/imap-login login_executable(pop3): /usr/lib/dovecot/pop3-login first_valid_uid: 9 mail_extra_groups: mail default_mail_env: mbox:~/mail/:INBOX=/var/mail/%u mail_location: mbox:~/mail/:INBOX=/var/mail/%u mmap_disable: yes lock_method: dotlock maildir_copy_with_hardlinks: yes mail_executable(default): /usr/lib/dovecot/imap mail_executable(imap): /usr/lib/dovecot/imap mail_executable(pop3): /usr/lib/dovecot/pop3 mail_plugin_dir(default): /usr/lib/dovecot/modules/imap mail_plugin_dir(imap): /usr/lib/dovecot/modules/imap mail_plugin_dir(pop3): /usr/lib/dovecot/modules/pop3 pop3_uidl_format(default): pop3_uidl_format(imap): pop3_uidl_format(pop3): %v.%u auth default: mechanisms: digest-md5 cram-md5 login passdb: driver: ldap args: /etc/dovecot/dovecot-ldap.conf userdb: driver: ldap args: /etc/dovecot/dovecot-ldap.conf socket: type: listen client: path: /var/spool/postfix/private/auth mode: 432 user: postfix group: postfix

Any ideas welcome :-)

-- Udo Rader

bestsolution.at EDV Systemhaus GmbH http://www.bestsolution.at