Hy, I have the last non-unibody 2.4Ghz MacBook Pro, upgraded to 4GB of RAM and recently, an SSD. The next upgrade I have planned in the future (maybe a Christmass gift) is to replace one of the RAM slots with a 4GB version, for a 6GB total. Now, the one thing I would need this RAM for is disk cache. I do a lot of compilations that touch a whole lot of files (think of 1GB of source code) so using this RAM as disk cache (not ram disk) would be nice. The thing is I'm not entirely sure how good OSX' memory management is. I know that on a Linux server most of the free memory will be used as disk cache but this doesn't seem to be the case on OSX. For example, right now (while browsing) I seem to have 1GB of free RAM according to Activity Monitor. So, is the upgrade to 6GB worth it ?