Dual Xeon EM64T crashes reliably w/ 5.x amd64

[Claus Guttesen]

> cooling, yes. You can see my previous posts for more info, but in
> short, we run php apache-1.3, postgresql-8.0.3, perl-5.8.6 (amavisd),
> postfix, named, clamd. httpd is very busy.
> 
> CPUTYPE?=nocona
> CFLAGS= -O -pipe
> COPTFLAGS= -O -pipe

I have CPUTYPE=nocona, CFLAGS= -O2 -pipe -funroll-loops and COPTFLAGS=
-O2 -pipe -funroll-loops, but that should not make any difference.

> Kernel is generic except some small details, see
> http://lists.freebsd.org/pipermail/freebsd-amd64/2005-May/004949.html
> I don't have many temp files, doubt it is the problem. It can be an
> out-of-memory situation, possibly... I realize now it is swapping, 25%
> of swap used. Must get more memory, I guess... can the machine crash
> that hard when out of memory???

I saw the dmesg and noticed this at the bottom:

Interrupt storm detected on "irq18: uhci2"; throttling interrupt source
Interrupt storm detected on "irq16: uhci0"; throttling interrupt source

This indicates USB, if so try adding usbd_enable="NO" to /etc/rc.conf.

Try limiting the amount of clients able to connect to your webserver,
so you can serve those which do get access well. I have the following
in my /usr/local/etc/apache/httpd.conf (I'm using apache):

KeepAlive Off
MaxClients 50

MaxClients is (avail. RAM / size of each process) minus some
housekeeping. Your server should not swap. Since KeepAlive is off it
can serve more clients than 50.

> Would abandoning amd64 and installing a i386 system help? Probably yes?
> I'd rather not, that's a substantial amount time to reinstall
> everything... :(

Don't know, but amd64 appears faster than i386 (when you can go with
dual of course).

Claus