imap-processes are not terminating

[Jan Kowalsky]

Hi all,

we have a situation where we see a increasing number of imap-processes
during the time. It seems that some clients don't terminate their
connections correctly.

We have about 500 User and on a normal day there are about 150-200
parallel connections. But there is a increasing number of processes up
to 30 days and older (if we don't restart cyrus) so that the total
number of processes reaches more than 1000 and meets the limit of memory.

There are some curiosities: inspecting processes with strace we see,
that most of them belong to only a few users and again are related to
only some folder. Most popular: the drafts folder.

Because of the network connections (some are at the same time logged in
via dsl-provider and g3 networks) we guess they come from smartphone
clients.

Is there any possibility to set a timeout or a max. duration for an
connection in cyrus?

Anybody else has the same experience?

Best Regards
Jan