Hi All,

I have recently moved by webmail server from a VPS to a hosted dedicated server running Ubuntu 16.04. Everything is fine except that login is particularly and consistently long (around 4-5 seconds).

I have noticed that the process dovecot/auth seems to eat all of the resources of one of the cores available on the host during login. The authentication backend is a postgres database which is running absolutely fine.

I have been scavenging on the dovecot mailing list for some time but I have not been able to find a solution to my problem so decided to send this bottle to the sea.

Here is my config: $ sudo dovecot -n # 2.2.22 (fe789d2): /etc/dovecot/dovecot.conf # Pigeonhole version 0.4.13 (7b14904) # OS: Linux 3.14.32-xxxx-grs-ipv6-64 x86_64 Ubuntu 16.04.1 LTS ext4 auth_cache_size = 10 M auth_mechanisms = plain login default_internal_user = vmail first_valid_uid = 0 mail_location = maildir:/home/data/vmail/%d/%n mail_plugins = " fts fts_solr" mail_privileged_group = vmail maildir_stat_dirs = yes managesieve_notify_capability = mailto managesieve_sieve_capability = fileinto reject envelope encoded-character vacation subaddress comparator-i;ascii-numeric relational regex imap4flags copy include variables body enotify environment mailbox date index ihave duplicate mime foreverypart extracttext namespace inbox { inbox = yes location = mailbox Archive { auto = subscribe special_use = Archive } mailbox Drafts { auto = subscribe special_use = Drafts } mailbox Junk { auto = subscribe special_use = Junk } mailbox Sent { auto = subscribe special_use = Sent } mailbox "Sent Messages" { special_use = Sent } mailbox Trash { auto = subscribe special_use = Trash } prefix = } passdb { args = /etc/dovecot/dovecot-sql.conf.ext driver = sql } plugin { antispam_backend = pipe antispam_mail_notspam = learn_ham antispam_mail_sendmail = /usr/bin/rspamc antispam_mail_sendmail_args = -h;localhost:11334;-P;q1 antispam_mail_spam = learn_spam antispam_spam = Junk antispam_trash = Trash fts = solr fts_solr = break-imap-search url=http://localhost:8080/solr/ sieve = file:~/sieve;active=~/.dovecot.sieve sieve_before = /var/lib/dovecot/sieve.d/ } postmaster_address = postmaster@domain.net protocols = imap lmtp sieve pop3 service auth-worker { unix_listener auth-worker { user = vmail } user = vmail } service auth { unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0666 user = postfix } unix_listener auth-userdb { group = vmail mode = 0660 user = vmail } user = vmail } service imap-login { inet_listener imap { port = 0 } service_count = 1 } service lmtp { unix_listener /var/spool/postfix/private/dovecot-lmtp { group = postfix mode = 0666 user = postfix } user = vmail } service pop3-login { inet_listener pop3 { port = 0 } } ssl = required ssl_cert =