Debian server: “sa-learn” process slows system down dramatically

amavisdebianspamassassin

On one of our debian squeeze servers, we use a setup of postfix + amavis + dovecot as mailserver. Spamassassin is part of amavis.

Once a day, the process "sa-learn" is started. It is part of spamassassin, training the bayesian filter for it. A good thing, but unfortunately, it exhausts the servers ressources dramatically – the load goes up from 0.5 to 12, the server becomes unresponsive. I have to kill the sa-learn process.

What can I do about it? Is there any chance to make sa-learn behave nice? If there isn't, where can I disable sa-learn? (I did not find any cron start script – the only reference to sa-learn I found is in /usr/sbin/amavisd-new-cronjob, which I commented out with no effect.

Best Answer

I had a similar issue with response time, until I found out that the SpamAssassin database requires some minimal ongoing maintenance. Are you issuing

sa-learn --force-expire

on a daily basis? It could be that a lack of maintenance has made the database unweildy and it needs to be "trimmed up a bit". Try placing it in a daily cron job and see if the response is better on the next sa-learn run.

Related Solutions

Debian – How to check for modified config files on a Debian system

To find all Debian managed configuration files which have been changed from the default you can use a command like this.

dpkg-query -W -f='${Conffiles}\n' '*' | awk 'OFS="  "{print $2,$1}' | md5sum -c 2>/dev/null | awk -F': ' '$2 !~ /OK/{print $1}'

Edit (works with localized systems):

dpkg-query -W -f='${Conffiles}\n' '*' | awk 'OFS="  "{print $2,$1}' | LANG=C md5sum -c 2>/dev/null | awk -F': ' '$2 !~ /OK/{print $1}' | sort | less

Edit (works with packages with OK in the filename):

dpkg-query -W -f='${Conffiles}\n' '*' | awk 'OFS="  "{print $2,$1}' | LANG=C md5sum -c 2>/dev/null | awk -F': ' '$2 !~ /OK$/{print $1}' | sort | less

Debian 5 server is randomly shutting down

Someone could be pressing the power button performing ACPI shutdown or it just might be an issue with ACPI. The system could also have sensor problems and thus thinks it is becoming to hot and shutsdown.

Try setting acpi to off in the kernel boot options. This is most likely performed in grub(/boot/grub/menu.lst).

You should look for the section that looks like:

title           Debian GNU/Linux, kernel 2.6.26-2-amd64
root            (hd0,0)
kernel          /boot/vmlinuz-2.6.26-2-amd64 root=/dev/sda1 ro
initrd          /boot/initrd.img-2.6.26-2-amd64

Add acpi off to the kernel line like this:

   kernel          /boot/vmlinuz-2.6.26-2-amd64 root=/dev/sda1 ro acpi=off

Reboot and try out your new setting!

EDIT: if it is an ACPI issue you may find more info in the log file:

 /var/log/acpid

Best Answer

Related Solutions

Debian – How to check for modified config files on a Debian system

Debian 5 server is randomly shutting down

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