I suspect, that dovecot v2.0.16 under Linux (tested on Gentoo 3.0.4 Hardened, Gentoo 3.0.6, Gentoo 3.1.4) causes 100% cpu utilization when index.cache is broken and doveadm is lanched. Dovecot uses LDAP as the userdb and provides IMAP and LDA. Because each user has a quota, the doveadm's expunge functionality is used to get rid of old trashed mail.
The mail log: Dec 12 07:38:59 www dovecot: imap(user): Error: Corrupted index cache file /var/data/mail/domain.tld/user/mail/dovecot.index.cache: invalid record size
Doveadm is launched as: doveadm -D expunge -A mailbox Trash savedbefore 1w
Mail is stored on ext4 and flush will use all of the CPU capacity like this: load average: 4.00, 4.01, 4.05
ps: root 26401 98.2 0.0 0 0 ? R Dec20 1369:49 [flush-253:1]
lsblk: vg_data-mail (dm-1) 253:1 0 500M 0 /var/data/mail
dovecot -n: # 2.0.16: /etc/dovecot/dovecot.conf # OS: Linux 3.0.4-hardened-r5 x86_64 Gentoo Base System release 2.0.3 auth_debug = yes auth_debug_passwords = yes auth_verbose = yes hostname = mail.domain.tld lda_mailbox_autocreate = yes lda_mailbox_autosubscribe = yes listen = * mail_debug = yes mail_gid = vmail mail_home = /var/data/mail/domain.tld/%n mail_location = maildir:~/mail mail_plugins = " mail_log notify zlib quota" mail_uid = vmail 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 ihave passdb { args = /etc/dovecot/dovecot-ldap.conf.ext driver = ldap } plugin { autocreate = Sent autocreate2 = Trash autocreate3 = Spam autosubscribe = Sent autosubscribe2 = Trash autosubscribe3 = Spam fts = squat fts_squat = partial=4 full=10 quota = maildir:User quota quota_rule = *:storage=100M quota_rule2 = Trash:ignore quota_warning = storage=95%% quota-warning 95 %u quota_warning2 = storage=80%% quota-warning 80 %u sieve = ~/.dovecot.sieve sieve_dir = ~/sieve sieve_quota_max_scripts = 5 sieve_quota_max_storage = 5M } postmaster_address = postmaster@domain.tld protocols = imap sieve service auth { unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0660 user = postfix } unix_listener auth-userdb { group = vmail mode = 0600 user = vmail } } service quota-warning { executable = script /etc/dovecot/quota-warning.sh unix_listener quota-warning { user = vmail } user = vmail } ssl_cert =
userdb { args = /etc/dovecot/dovecot-ldap.conf.ext driver = ldap } verbose_proctitle = yes verbose_ssl = yes protocol lda { info_log_path = log_path = mail_plugins = " mail_log notify zlib quota sieve" } protocol imap { mail_plugins = " mail_log notify zlib quota autocreate fts fts_squat imap_zlib imap_quota" }
dovecot-ldap.conf.ext: hosts = localhost dn = user dnpass = pass base = base auth_bind = yes user_attrs = homeDirectory=home,uidNumber=uid,gidNumber=gid,mailboxQuota=quota_rule=*:bytes=%$ user_filter = (&(objectClass=inetOrgPerson)(uid=%u)) pass_attrs = uid=user pass_filter = (&(objectClass=inetOrgPerson)(uid=%u)) iterate_attrs = uid=user iterate_filter = (objectClass=inetOrgPerson)
I suspect, that this is something to do with Dovecot, because after deleting the dovecot.index.cache file, everything went back to normal. When this happens, I cannot unmount the drive nor a system reboot works.
Thank you !