[oblio]

I think his point is that you can "run" a large amount of applications at the same time on a CPU. It will execute everything, albeit slowly. This might not be acceptable for performance concerns, but it's doable.

He's not talking about actual data compression in RAM. Because even with compression, with current OSes, if you try to fit more than 20GB of data, let's say becoming 10GB compressed, into 5GB of RAM, it's not possible. You have to swap and at that point your performance is completely gone.

The performance gap between an overloaded CPU and swapping is humongous. One is annoying or slightly troublesome, the second is a death knell.