System load spike on dovecot reload

[dave at evilcigi.eu]

Hi everyone,

I'm running dovecot with quite a lot of users and lots of active imap 
connections (like 20'000). I'm using different user IDs for users, so I 
need to have imap {service_count=1} - i.e. I have a lots of imap 
processes running.

Everything works fine, until I reload dovecot configuration. When that 
happen, every client is forced to relogin in the same time and that 
causes a huge system load spike (2-3000 5 min load).

I was thinking that it would be great, if dovecot wouldn't kick all the 
users in the same time during reload, but somehow gradually, during 
specified interval. I'm aware of the shutdown_clients directive that 
could help, but I don't like it - I do want the clients get disconnected 
on dovecot shutdown and also I want them to relogin in reasonably short 
time after reload.

Is something like that possible with dovecot or does it make sense to 
implement that in the future versions?

Thank you.

Dave.