I recently upgraded my Mid-2010 Macbook to 8gb of ram. Everything is working great only thing questioning to me is when I go to activity tracker with everything closed except the tracker it is showing almost 4gigs being used. This just seems odd to have so much being accessed with no programs running. It shows lots of processes using small amounts but I'm not aware of what many of these things are operating. Any advice? In this screen shot there is Google Chrome open.