FreeBSD 10 & default_vsz_limit causing reboots?

Timo Sirainen tss at
Thu Sep 24 18:58:20 UTC 2015

On 24 Sep 2015, at 16:26, Rick Romero <rick at> wrote:
> Update.  Only a single reboot has occurred since changing
> defalt_vsz_limit from 384M to 512M.  It would seem that something the
> users are doing is causing that virtual memory size to be exceeded
> (possibly a mailbox search?), and when that occurs Dovecot/FreeBSD is not
> handling the event as smoothly as expected.

I could maybe understand that a system might reboot in some conditions when it runs out of memory, but you're doing the exact opposite of avoiding that by increasing the vsz limit. It just means that the system is potentially going to use even more memory. And wouldn't FreeBSD have something similar to Linux's out-of-memory killer?

I think either your hardware is broken or FreeBSD has some serious bug, and a hardware problem seems more likely to me.

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