Cyrmaster at 100% cpu, defunct processes, connection timeouts

[Vladislav Kurz]

On 14/03/2019 10:45, Vladislav Kurz wrote:
> Hello everybody
> 
> yesterday evening I have update a server with ubuntu 18.04 (just the routine 
> security update, libc, kernel, not cyrus), and after reboot cyrus fails in 
> quite strange way.
> 
> It works fine for a few minutes, but then the cyrmaster spins up to 100% cpu 
> (1-core), and stops receiving new connections. Processes that exit stay in 
> defunct/zombie state, and eventually all of them end up like that.
> 
> At first I suspected some SSL problems, so eptied the tls_sessions.db, even set 
> tls_session_timeout: 0, tried to disable mailnotifier (I had it at log), 
> enabled debug, but still can't find the problem. 
> 
> Anybody has/had the same problem and perhaps a solution?

replying to myself, changing to prefork=1 (instead of prefork=0) solved
the issue.

I vaguely remembered that I changed to prefork=0 to fix some previous
problems...

For completenetes:

cyrus-imapd                           2.5.10-3ubuntu1
libc6:amd64                           2.27-3ubuntu1
linux-image-4.15.0-46-generic         4.15.0-46.49

-- 
Best regards
        Vladislav Kurz