I have a VPS with 384MB RAM available as standard, and the option to burst up to 1GB.
This is enough to run some fairly high traffic sites if you’re careful with the setup, but with the default setups and fancy control panels, you’ll exceed the memory limit quite quickly.
I use Citadel as the email client, but I’ve disabled Webcit. I also removed Spam Assassin, and just use the Realtime Blackhole List to prevent spam. Those simple changes have shaved over 100MB off my normal usage, but there’s still a lot to go.
top shows that memory usage is leaking up into the burst limit over time – even with some basic optimizations of httpd.conf and MySQL. I’m considering trying lighttpd instead of Apache2 – I really don’t NEED Apache2, and it seems to be quiet a hog.
The other possible optimization would be to use something lightweight in place of named – which is currently sat at 180m memory usage!
If anyone has any favourite lightweight alternatives to named, I’d love to hear about them.