sos on cyrusimapd

[Albert Shih]

Hi everyone,

So today I switch all my user from my old server to the new one running
cyrus-imapd 3.0.7 with FreeBSD 11.1-p11.

The server get 192Go of Ram.

Currently I got lot of disconnection from MUA (mutt), the client going to
keep the connection during let's say few minutes and then I lost the
connection (nothing to do with the network).

If I relaunch just after de disconnection, I can get

  back maibox pretty quickly,
  back maibox very slowly
  connection error (strange SSL I/O error on the client)

On the server I didn't see lot of message, only this strange

  onewconn: pcb 0xfffff8276c40e570: Listen queue overflow: 49 already in queue awaiting acceptance (209 occurrences)

knowing I'm not able to find the pcb fffff8276c40e570 with netstat or lsof,
event it not change in time.

I guessing I mis configure something...but what ?

I know the server are under heavy load because all my user's client are
re-synchronize their mailbox. But well It's not very good...

Is anybody running cyrusimapd on FreeBSD have tuning some special variable
in the kernel through sysctl ?

Regards

--
Albert SHIH
Observatoire de Paris
xmpp: jas at obspm.fr
Heure local/Local time:
Wed Jun 27 16:03:10 CEST 2018