How to tweak apache2/mysql to run a large SMF forum nicely?

@bros:

I'm on a Linode 512. The SMF forum has like 4-5k unique visitors a month, around 10-50 on at a time.

In apache, mpm_prefork is set to:

StartServers 1

MinSpareServers 3

MaxSpareServers 5

MaxClients 20

MaxRequestsPerChild 0

mpm_worker is set to:

StartServers 2

MaxClients 350

MinSpareThreads 25

MaxSpareThreads 75

ThreadsPerChild 25

MaxRequestsPerChild 0

Are those good? Also, what settings should I modify in mysql?

which one are you using? mpmprefork or mpmworker? Only one of those settings will be in use at any time.

apache2 -v | grep MPM will tell you

Have you considered using nginx? With the right configuration you will be able to get a lot more out of your box performance wise.