Hi Francesco,
At 00:34 19-09-2008, Vincenti Francesco wrote:
>My system has the following characteristics:
>- A two nodes cluster based, active-active, one for the
>incoming email and the other for the outgoing email. If a node
>crashes, the other brings the service on its shoulders.
>- Each node has 4GB RAM and two processors
>- O.S. Fedora core 3
>- Mail server qmail 1.0.3
>- Antivirus clamav 0.87.1
>- Antispam spamassassin 3.0.4
>- Cluster controller heartbeat
>- Interface qmail-scanner-queue.pl

That version of SpamAssassin is quite old.

>Starting from the 15th of July, I find, sometimes, in the log file
>of qmail-scanner-queue.pl the following alert instead of normal
>score: SA: finished scan in 600.010015 secs - hits=?/?.
>I have already searched on the official site of spamassassin and it
>seems to be generated by some kind of trouble using the web
>scansion. I really used pyzor and razor2 scansion, so I took them
>out from local.cf. This action caused the decrease of average
>processing time from 15 seconds to 3.5 seconds for each treated
>email. But I still have some kind of web search because the system
>is configured to use RBL search too, and I can't take it out. The
>time has been improved but the problem stays!
>I have to write and to upgrade a local configuration file, named
>local_rules.cf which has reached the dimension of 250KB it is very
>useful to stop a lot of SPAM which is not stopped by the other
>rules. The problem started to appear after one of the upgrade I
>usually have to do, which wasn't so dramatic to justify this
>behaviour, I think.

I gather that you have read
http://wiki.apache.org/spamassassin/FasterPerformance The large
local rules file will affect performance. If you want to keep pyzor
and razor2, see http://wiki.apache.org/spamassassin/UsingNetworkTests
on how to reduce the timeout values. Run spamd with the -D switch to
find out whether there are any errors.