Spamassassin is slow - any tips or good commercial alternative?

Martin.Hepworth martinh at
Fri Jun 13 09:34:43 IST 2008



Also check you've got the spamassassin cache working OK - you'll

Need the perl module DB_File installed for this to work (check with MailScanner -v)

But to be honest I'd say 5-10 seconds for a batch ain't too bad.

I'd check how many children you've got and how many in the batch.

I'd also drop the spec of the machine here so we can see if there's anything obvious we can recommend.

Martin Hepworth
Snr Systems Administrator
Solid State Logic
Tel: +44 (0)1865 842300

> -----Original Message-----
> From: mailscanner-bounces at
> [mailto:mailscanner-bounces at] On Behalf
> Of Charlie
> Sent: 13 June 2008 08:12
> To: MailScanner discussion
> Subject: Spamassassin is slow - any tips or good commercial
> alternative?
> >>I run an email server (Exim) which uses Mailscanner in combination
> >>with ClamAV and SpamAssassin. The server scans about 15,000
> emails per day.
> >>SpamAssassin currently seems to take 5-10 seconds to scan even the
> >>smallest email, which is unacceptable for us.
> >May I ask why? Is it because your mail system is getting into load
> >trouble? Or is the delay itself on legit mail the problem? I
> would like
> >to know how an additional 5-10 seconds on an async
> communication medium
> >like e-mail that was never designed for real-time in the first place
> >could be a problem.
> It is not really a problem except during peak hours, where
> there can be numerous emails sent every 1-2 seconds. These
> emails then pile up on eachother, and eventually cause the
> mail queue to grow very long, with emails taking 8-15
> *minutes* to actually leave the queue. It is then a very
> serious problem.
> >If it is a load problem you should try to reduce the amount of mail
> >reaching SpamAssassin in the first place. RBLs come to mind.
> Or (since
> >you asked for a commercial solution) have a look at BarricadeMX from
> >FSL. BMX will greatly reduce the amount of mail reaching your MTA.
> Our userbase means that over 99% of emails sent through the
> server are *not* spam, so any limiting of the emails reaching
> the MTA would not help.
> >Yet on the other hand, if the 15.000 mails a day that your
> server scans
> >are mostly ham, this will not help. So please enlarge a bit on the
> >problem itself.

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