Why does memory appear near full even after upgrade? I've just upgraded my MacBook Pro from 4GB to 8GB. Before the upgrade, I looked in the Activity Monitor and it said that it was using almost 3.98GB of 4GB (I'm a web developer, so I usually have lots of apps open.) Then after the upgrade Activity Monitor shows that it is using about 7.50GB of 8GB (with the same apps opened.) The upgrade improved the performance of the Mac, it is surprisingly faster than before, but I was hoping to see more memory available after this upgrade.

Thanks for your help!
The old days keeping as much RAM free as possible are gone.

The new RAM management from OS X, use all available memory, but also manages it so that you get maximum performances.

If you look in the Activity Monitor- memory, you will see things like Memory Pressure, Compressed among other information.