On 3. Feb 2025, at 20.18, Anatoliy Zhestov via dovecot <dovecot@dovecot.org> wrote: > >> >> Are you sure the problem is authentication / pgsql? You could test with >> looping "doveadm auth lookup $user" rapidly. Of course for different users >> to avoid them coming from cache. Or if you can reproduce it that way, try >> if the same happens for repeating the same user so it does come from cache. > > > i test in condition when 90% of imap connection is already established. > auth cache is enabled so i guess tests with the same user are not relevant. > > -------- less loaded server > ps waux|grep imap-login|wc -l > 24977
Oh, somehow I missed that you have this many concurrent connections. > echo "13285 / 343" |bc > 38 (per second) So with this speed 24977 users would take 11 minutes to login back, which is a bit slow. Some ideas: 1) If pgsql is the bottleneck, try multiple pgsql connections: Add maxconns=4 (or whatever) to the dovecot-sql.conf.ext's connect line. 2) In your Dovecot proxy (assuming you have one?) you can configure it to spread over disconnections over a long time, if the issue is that backend disconnects everyone at once. login_proxy_max_disconnect_delay setting does this. 3) With that many connections and to make logins faster, you'd be better off using https://doc.dovecot.org/2.3/admin_manual/login_processes/#high-performance-mode 4) To optimize login performance, it would be best to get rid of the post-login script. Also: service imap { service_count = 1000 process_min_avail = 10 } 5) auth_cache_size is rather small. Likely could be increased much larger. _______________________________________________ dovecot mailing list -- dovecot@dovecot.org To unsubscribe send an email to dovecot-le...@dovecot.org
