On 29 Nov 2016, at 2.57, Christian Balzer chibi@gol.com wrote:
service imap { # Most of the memory goes to mmap()ing files. You may need to increase this # limit if you have huge mailboxes. #vsz_limit = $default_vsz_limit vsz_limit = 512M
# Max. number of IMAP processes (connections) #process_limit = 1024 process_limit = 524288 }
..
But adding a "service_count = 100" line (any value larger than 1 really) to the imap section we get the dreaded:
Nov 28 17:05:40 mbx09 dovecot: config: Warning: service auth { client_limit=16384} is lower than required under max. load (528384)
- Where's the difference in Dovecot's logic between a mail service that has a service count of 1 versus one with >1?
With service_count=1 it disconnects from auth immediately after logging in. With service_count>0 the auth connection is kept open for the entire existence of the imap process. This is mainly because after dropping privileges it wouldn't be able to connect to the auth-master socket again. In theory if the socket permissions were changed, it could keep reconnecting to auth-master and not keep connections open all the time.
- Any way to get the process recycling for IMAP going w/o setting the fd limit to a ridiculous amount?
How about shrinking the imap process_limit? I highly doubt you can actually run 500k imap processes per server and have it still working. The largest I've ever heard people running has been 50k processes per server.