I have two servers pointing to an NFS mounted mail spool with dovecot. Since I recently switched from using Dovecot v1.X, I have been experiencing high CPU use with the two Dovecot servers. I am not certain why they are not well behaved. Here is the configuration information.
This configuration is currently running at a load average of 17.
/usr/sbin/dovecot -n # 2.1.15: /etc/dovecot/dovecot.conf # OS: Linux 3.10.54-server-2.mga3 i686 Mageia 3 base_dir = /var/run/dovecot/ disable_plaintext_auth = no lock_method = dotlock login_greeting = SpamZapper Email ready. login_log_format_elements = user=<%u> method=%m rip=%r lip=%l %c mail_debug = yes mail_fsync = always mail_location = maildir:~/Maildir mail_nfs_index = yes mail_nfs_storage = yes mail_privileged_group = mail mbox_lock_timeout = 15 mins mmap_disable = yes passdb { driver = pam } protocols = imap pop3 service anvil { client_limit = 203 process_limit = 1 } service auth { user = root } service imap-login { chroot = login client_limit = 10 user = dovecot vsz_limit = 256 M } service pop3-login { chroot = login client_limit = 20 user = dovecot } ssl = no syslog_facility = local2 userdb { driver = passwd } verbose_proctitle = yes protocol pop3 { mail_max_userip_connections = 20 pop3_logout_format = top=%t/%p, retr=%r/%b, del=%d/%m, size=%s pop3_uidl_format = %08Xv%08Xu } protocol lda { postmaster_address = postmaster@example.com } protocol imap { mail_max_userip_connections = 10 }
And the other server which is currently running with a load average of 10.
dovecot -n # 2.2.13: /etc/dovecot/dovecot.conf doveconf: Warning: service anvil { client_limit=100 } is lower than required under max. load (303) # OS: Linux 4.1.15-server-2.mga5 x86_64 Mageia 4 base_dir = /var/run/dovecot/ disable_plaintext_auth = no listen = * lock_method = dotlock login_greeting = SpamZapper Email ready. login_log_format_elements = user=<%u> method=%m rip=%r lip=%l %c mail_fsync = always mail_location = maildir:~/Maildir mail_nfs_index = yes mail_nfs_storage = yes mail_privileged_group = mail mmap_disable = yes passdb { driver = pam } protocols = imap pop3 service anvil { client_limit = 100 process_limit = 1 } service auth { user = root } service imap-login { chroot = login client_limit = 48 user = dovecot vsz_limit = 256 M } service pop3-login { chroot = login client_limit = 50 user = dovecot } ssl = no syslog_facility = local2 userdb { driver = passwd } verbose_proctitle = yes protocol pop3 { mail_max_userip_connections = 50 pop3_logout_format = top=%t/%p, retr=%r/%b, del=%d/%m, size=%s pop3_uidl_format = %08Xv%08Xu } protocol lda { postmaster_address = postmaster@example.com } protocol imap { mail_max_userip_connections = 40 }
Can you please offer a suggestion on what is happening? The timeouts to the imap server are frequent due to the load average.
Thank you.
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