FreePBX App Memory a little high

I recently installed FreePBX on a Rackspace Cloud server, 256 MB of RAM. The App Memory shows 75% after a day or two. I upgraded to 512 MB of RAM and it looks a little better. Is there something I can look at to see what is hogging all the memory or is this normal? I have a feeling that a whole bunch of unnecessary processes are running, I’m just not sure as to which processes FreePBX depends on.
Asterisk 1.2.6 with FreePBX 2.7.

Thanks in advance