I got a stupid memory question. When I run make or anything that takes a lot of memory, I see my 512 ram go down to about 50 free. Now thats not the bad part, the bad part is that it stays that way, or some times goes up, but very slow. Now the memory is in Inact mode, as top says(the memory just used) Now does that mean inactive? Can this memory be used? I checked man, but no real explanation.

To paraphrase one of the man pages, "Free memory is wasted memory". FreeBSD attempts to use whatever memory is not currently being used for disk caches and other buffers.

If you want an accurate measure of memory utilization, look at the output of `vmstat -c 2 -w 2 | tail -1 | cut -c 7-14`; that will give you the amount of memory (in kB) which belong to processes which are running or have been running in the past 20 seconds.

hey, thanks, that really cleared some things up