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Obsolete Releases => SME Server 7.x => Topic started by: ianhobson on May 11, 2009, 12:59:39 PM

Title: SME in small memory
Post by: ianhobson on May 11, 2009, 12:59:39 PM

Hi all,

Over the years SME has grown and the memory capability of my firewall has not. My Firewall is a Compaq deskpro and the BIOS will not recognise any more than 256MB.

This has been fine - up to today. Today, about 6am, it started to page swap and it is still doing it! It appears that some piece of filth has arranged that I get the backscatter from his spamming :(. I know I can't stop this.

What I can do - until I can replace the machine - is slim SME 7.4 down to a minimum memory use.

It handles email, spam filtering, and firewall duties mainly. Also DHCP and DNS resolution. No websites, no file sharing, no lvm no raid, no web-mail.

How can I remove the unwanted parts, so that SME can cope with the abuse its getting?

Thanks

Ian

Title: Re: SME in small memory
Post by: cactus on May 11, 2009, 03:01:46 PM

Quote from: ianhobson on May 11, 2009, 12:59:39 PM

It handles email, spam filtering, and firewall duties mainly. Also DHCP and DNS resolution. No websites, no file sharing, no lvm no raid, no web-mail.

Of which virus checking and spam checking are by far the most resource hungry functions, but I can understand you do not want to disable them.

Title: Re: SME in small memory
Post by: Knuddi on May 11, 2009, 08:45:56 PM

I think there is little you can do I am afraid. One service which you might be able to stop is the HTTP deamon (and you loose server-manager) as well. Secondly mysql maybe when webmail is not active. But I think this will give you very little.

Try to start "top" and press "M" - its now sorted by memory usage. Maybe you see something..

Title: Re: SME in small memory
Post by: janet on May 12, 2009, 09:37:32 AM

ianhobson

You can slow down the email processing so that memory limitations are not exceeded.
Change the number of concurrent messages that qpsmtpd & qmail handle.

Here's one db command, search on concurrency for more

db configuration setprop qmail ConcurrencyRemote 5
signal-event email-update

Title: Re: SME in small memory
Post by: janet on May 12, 2009, 09:44:32 AM

ianhobson

Also do you have RBL's enabled, and executable content rejection enabled ?

That will stop a lot of rubbish coming in, which will not need to be processed and therefore not use RAM & CPU power.

Disabling virus scanning and/or spam filtering will give you back your RAM.
That may seem a crazy thing to do, but if you have all the "front door rejection" methods enabled, then virus scanning and spam filtering will have much less to do, and at least your server will keep running on the RAM it has.

Importantly though, is to slow down the email processing speed as per previous post. Try a setting of 1. Even 256Mb of RAM will handle that OK.

Title: Re: SME in small memory
Post by: janet on May 12, 2009, 09:48:32 AM

ianhobson

As far as disabling & stopping unused services goes, yes that's appropriate to do, but keep in mind a service that is enabled but is doing nothing uses very little RAM or CPU power, so any gains will be minimal.

Slowing down incoming email is the most practical and effective answer.

Title: Re: SME in small memory
Post by: janet on May 16, 2009, 04:22:06 PM

ianhobson

Did you fix your problem, if so how ?