I'm no expert, but it may have something to do with the compressed memory thingy in OS X 10.9

Doing more

The more memory your Mac has at its disposal, the faster it works. But when you have multiple apps running, your Mac uses more memory. With OS X Mavericks, Compressed Memory allows your Mac to free up memory space when you need it most. As your Mac approaches maximum memory capacity, OS X automatically compresses data from inactive apps, making more memory available

 

Exrta Fast

Once the memory is compressed, your Mac doesn’t have to waste time continually transferring data back and forth between memory and storage. So it’s able to get more done in less time. And since compressing and decompressing happens almost instantly, the only thing you’ll notice is how responsive everything feels. Especially when you’re doing everything at once.

^{Source: http://www.apple.com/osx/advanced-technologies/ (non-existing)}

See also: OS X Mavericks is more than Powerful: It’s Power Smart (PDF)

They may have done that do avoid the older program from interfeering with the new way of doing things. But I have no idea.

I'm no expert, but it may have something to do with the compressed memory thingy in OS X 10.9

Doing more

The more memory your Mac has at its disposal, the faster it works. But when you have multiple apps running, your Mac uses more memory. With OS X Mavericks, Compressed Memory allows your Mac to free up memory space when you need it most. As your Mac approaches maximum memory capacity, OS X automatically compresses data from inactive apps, making more memory available

Exrta Fast

Once the memory is compressed, your Mac doesn’t have to waste time continually transferring data back and forth between memory and storage. So it’s able to get more done in less time. And since compressing and decompressing happens almost instantly, the only thing you’ll notice is how responsive everything feels. Especially when you’re doing everything at once.

^{Source: http://www.apple.com/osx/advanced-technologies/ (non-existing)}

See also: OS X Mavericks is more than Powerful: It’s Power Smart (PDF)

They may have done that do avoid the older program from interfeering with the new way of doing things. But I have no idea.

I'm no expert, but it may have something to do with the compressed memory thingy in OS X 10.9

http://www.apple.com/osx/advanced-technologies/

Doing more

The more memory your Mac has at its disposal, the faster it works. But when you have multiple apps running, your Mac uses more memory. With OS X Mavericks, Compressed Memory allows your Mac to free up memory space when you need it most. As your Mac approaches maximum memory capacity, OS X automatically compresses data from inactive apps, making more memory available

Exrta Fast

Once the memory is compressed, your Mac doesn’t have to waste time continually transferring data back and forth between memory and storage. So it’s able to get more done in less time. And since compressing and decompressing happens almost instantly, the only thing you’ll notice is how responsive everything feels. Especially when you’re doing everything at once.

They may have done that do avoid the older program from interfeering with the new way of doing things. But I have no idea.

I'm no expert, but it may have something to do with the compressed memory thingy in OS X 10.9

Doing more

The more memory your Mac has at its disposal, the faster it works. But when you have multiple apps running, your Mac uses more memory. With OS X Mavericks, Compressed Memory allows your Mac to free up memory space when you need it most. As your Mac approaches maximum memory capacity, OS X automatically compresses data from inactive apps, making more memory available

Exrta Fast

Once the memory is compressed, your Mac doesn’t have to waste time continually transferring data back and forth between memory and storage. So it’s able to get more done in less time. And since compressing and decompressing happens almost instantly, the only thing you’ll notice is how responsive everything feels. Especially when you’re doing everything at once.

^{Source: http://www.apple.com/osx/advanced-technologies/ (non-existing)}

See also: OS X Mavericks is more than Powerful: It’s Power Smart (PDF)

They may have done that do avoid the older program from interfeering with the new way of doing things. But I have no idea.