Timeout for IMAP idle

[Thomas Jarosch]

Hello,

right now cyrus imapd (2.4 / 2.5) doesn't have a timeout for connections
in the "IDLE" state.

One mail server here is serving a lot of Android K9 mail clients
that make heavy use of IMAP idle. So far around 2300 imapd
processes piled up even though it's just about 100 users in total.
Some of those connections are in the IDLE state for two weeks now.

What about adding a configurable timeout for IMAP idle?

There were bugs in the past concerning Outlook Express
and at least Outlook 2007 showing an offline status
once the connection was closed on the server side.
Various IMAP servers had quirks for this.

Still an idle timeout of let's say 48h might make sense.

Cheers,
Thomas