Michael Svanström

developer, photographer

Dovecot process gone bezerk

Today I’ve had some serious battles with Dovecot running on a wild cpu time spending spree. I recently made an apt-get upgrade on my Debian system. Somwhere in there things went awkward. An imap process simply wouldn’t stop on /etc/init.d/dovecot stop nor kill -9 [dovecot-pid] The process took 100% cpu and eventually the whole system, including kernel, froze. Had to cold reboot it via IPMI three times! Thank god for IPMI.. Anyways I found this mailing thread with the same issue. What seems to have solved to problem for me was to upgrade Debian from lenny to unstable, including the latest Debian kernel ( and Dovecot 1:1.2.10-1 and keeping my fingers crossed while rebooting. I also noticed some complaints for a missing “cpusieve” plugin. Uncommenting plugin = cmusieve in dovecot.conf was necessary.