- SLES 10, GW 8.0.1 (upgraded from 8.0HP2 a week ago)
- Approx 500 clients using IMAP (Thunderbird), 50 clients using GW8 client, 50 clients using WebAccess

Since the installation of SP1 a week ago, the IMAP service on the POA randomly stops accepting connections. When the problem arises I can look at the status of the threads, and I can see that all threads are in use (for 200+ seconds and counting). Doing a '/etc/rc.d/grpwise status' shows that all services (PO and MTA) are running. When things are working normally, the IMAP threads process requests in under 3 seconds (usually under a second - extremely fast!).

I've noticed that no more than 8 IMAP threads are ever created. The default setting is to use as many as 40 threads.

I haven't been able to figure out two things in this situation:
1. What is happening to cause the IMAP service to take 200+ seconds to process a request? (Verbose logging hasn't been much help.) My theory is that if I wait long enough, the threads will release themselves, but I've witnessed one thread process a request for 900+ seconds. I'm not willing to let my clients wait that long so I can test my theory...:)

2. Why aren't more threads created?

I've also noticed that there was a change in IMAP behavior in SP1: Before SP1, an expunge process had to be run in Thunderbird to make "trashed" messages appear in the Trash folder. With SP1 that behavior has changed - messages now appear almost immediately in the Trash. (Could something else have changed to cause the IMAP problem I'm seeing?)

If you have any suggestions, please throw them out there!

Thanks!
Mike