port-amd64/46833: NetBSD 6.0_BETA2 shutdowns under load

[ftigeot%wolfpond.org@localhost]

>Number:         46833
>Category:       port-amd64
>Synopsis:       NetBSD 6.0_BETA2 shutdowns under load
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    port-amd64-maintainer
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Fri Aug 24 20:25:00 +0000 2012
>Originator:     Francois Tigeot
>Release:        NetBSD 6.0_BETA2
>Organization:
>Environment:
NetBSD netbsd.zefyris.com 6.0_BETA2 NetBSD 6.0_BETA2 (GENERIC) amd64
>Description:
I left a NetBSD 6.0-BETA2 system running PostgreSQL benchmarks. It
powered-off by itself with this message on console:

CRITICAL TEMPERATURE! SHUTTING DOWN

Hardware is a 1U dual Xeon X5650 system with 24 GB RAM (Dell R410).

Machine only gets slightly warm to touch under load; no other operating
system shows this behavior.


>How-To-Repeat:
Run pgbench in select mode with a large database and at least 20 client 
processes.
I can get NetBSD to shutdown in a matter of minutes 100% of the time
with this configuration:

- PostgreSQL 9.2-beta3
- Pgbench with a scale 800 database (~= 11GB)
- pgbench -h 127.0.0.1 -j 1 -c 24 -T 600 -S bench

(The last command runs 24 client processes for 10 minutes.)
>Fix: