Hi guys, i'm a macbook pro 13" user. The macbook has 8gb of ram, but when i open a 30-35mb pdf with default program of apple, Preview, the free ram falls down, and the swap area increase to almost 1gb! Is that a my problem or is this a pdf format problem? Has anyone ever had the same problem? I think 8gb isn't too much, but my brother has got a 2011 macbook pro 15 with 4gb of ram, and working with autocad he never has that problem! Waiting for answer. thanks PS. Sorry for my english, i'm an italian boy!