FBSD 6.2 Xeon 2.4ghz CPU and high load

[Chuck Swiger]

On May 9, 2008, at 11:55 AM, DAve wrote:
>> For single-processor systems, FreeBSD 4.11 does very well at a lot  
>> of tasks.  However, Dave apparently has a 4-CPU system (~8 threads  
>> if he enabled hyperthreading), and for real SMP hardware, more  
>> recent versions of FreeBSD generally perform better than 4.x would.
>
> Single CPU quad core.

OK.

> ps -aux output is up, look under the FBSD dir. I also put up both  
> dmesg.boot files from the servers.

MailScanner is what is taking up all of the load; tuning that area is  
where you need to focus.

Things which come to mind are trying to limit the max number of  
children of that being run to something smaller, perhaps 8 or so.   
Yes, they recommend running 5 * #CPUs, but they also think their  
instances are going to be around 20MB in size, but yours are running  
at 100+ MB size.

You might find that running sa-update and sa-compile nightly might  
improve your SpamAssassin performance; I've got a crontab setup which  
runs the following nightly:

% cat /usr/local/bin/update-spamassassin
#! /bin/sh

PATH=$PATH:/usr/local/bin

sa-update --allowplugins --gpgkey  
D1C035168C1EBC08464946DA258CDB3ABDE9DC10 --channel  
saupdates.openprotect.com --channel updates.spamassassin.org
sa-compile

kill -HUP `cat /var/run/vscan/spamd.pid`

(If you aren't running spamd because MailScanner uses builtin  
interface to SpamAssassin, comment out the last line.  But do check  
the sa-compile docs, you have to make a change for it to be used....)

Regards,
-- 
-Chuck