On 19-05-2010 14:03, Emerson Pinter wrote: > Hi all. > > I'm using Courier IMAP for 6 years in my mail servers. It's very stable. > Since last year, I'm looking for implementing IMAP IDLE in my email > system. > During my tests with 2 or 3 accounts under low load, imap idle worked > fine. > So I decided to enable IDLE in my production servers (using libgamin). > That day was a complete disaster. The server with Courier IMAP+IDLE > enabled, kept thousands of connections open with no activity until the > machine froze. > Once I disabled IDLE, the server returned to normal again. > > Note that IDLE is *supposed* to make the clients keep the connections open as long as they have their client programs open (which is all day for many people). So thousands of zero-traffic open connections just waiting for either end to have something to say is the normal behavior for any IMAP/IDLE server. This in turn implies that any server providing IDLE support will need to sustain a load of at least 1.5 (guestimate) connections per user, most of them doing nothing. This means that your system-wide limits on open TCP connections, processes etc. need to be at least that high (OK, some IMAP servers serve multiple connections per process to reduce the memory and process table load somewhat).
As for your other issues I have no idea if libgamin, famd, courier-imap or another component of your system uses polling or other such resource-eating methods when just waiting for a file change that might happen. And I don't know if there is a courier-imap 4.7.0 option to turn off the no-IDLE-because-no-fam alert ------------------------------------------------------------------------------ _______________________________________________ Courier-imap mailing list [email protected] Unsubscribe: https://lists.sourceforge.net/lists/listinfo/courier-imap
