Call it installation or call it caching, but the bottom line is that you will have to save large chunks of PlayStation 4 games to the system's hard drive. It's not an option. It's mandatory on Sony's next-gen system. Today, at a stylish waterfront hotel in New York City that's been taken over by Sony for all things PS4, the system's lead architect, Mark Cerny, explained just how these requirements work.
If you are playing a disc-based game, the system will begin caching the disc when you put it in the console and get ready to play. The game is saving part of itself to the system's hard drive. The amount of data that has to be saved before you can start will vary per title.
Cerny said that for the launch game he directed, Knack, users should only have to wait 10s of seconds to play the game. After that, as you play, the game will stream more content to the console's 500GB hard drive. Knack will use 37GB of space overall, as noted on the game's box. Obviously, it won't take many games to fill the console's hard drive.
Cached/installed game data will stay on the hard drive until the user deletes it. Cerny said that there had been some internal discussions at Sony about having the PS4 auto-delete installed data from games that players hadn't used in a while. They decided against it, figuring that gamers would never want to feel "blindsided" and would prefer to make their data management decisions manually. Probably a good choice!
The disc installation is required on PS4 because the console is not designed to read games off of discs. It's not a PlayStation issue. It's a physics issue. The machine may have a Blu-Ray drive that's about three times faster than the PS3 with about six times as much memory, but it's still more expedient for it to read data from its own hard drive. Cerny said his team had heard too many complaints from current-gen developers about having to wait to load in new levels of games. Putting the data on the readily-accessible hard drive alleviates that.
Not surprisingly, Microsoft's Xbox One requires installation from Blu-Ray, too, and only runs games off the hard drive.
If a PS4 user decides to download a game, they will have to wait longer to play. Cerny couldn't provide as narrow an estimate on how long a player who decided to download Knack would have to wait. That depends in large part on a user's Internet connection speed. Ideally, he said, they wouldn't have to wait more than an hour before beginning to play the partially downloaded games. Other games may be set up differently, allowing users to start playing them sooner or requiring them to wait longer. With these kinds of download speeds and requirements, players may want to queue their PS4 downloads long before they want to start gaming or download in the background while doing something else. Or just drive to the store and get a disc.
source
hopefully it goes quickly.