PlayStation 4 RAM Allocation Clarified By Sony

Last week, a report from Digital Foundry claimed that while the PlayStation 4 would come equipped with 8GB of DDR5 RAM, only a little over half of that would be available to use by developers. To put speculation to rest, Sony decided to offer some clarification.

The original report stated that developers would have access to 3.5GB worth of dedicated RAM. An additional 1GB of RAM would be available as “flexible” memory, and the remaining 3.GB would presumably be reserved for the PlayStation 4’s Operating System. Rather than going into specifics on how much memory will be allocated to what, Sony instead decided to clarify what “flexible” memory means.

Here’s the official explanation from Sony, as sent to Digital Foundry:

“We would like to clear up a misunderstanding regarding our ‘direct’ and ‘flexible’ memory systems. The article states that ‘flexible’ memory is borrowed from the OS, and must be returned when requested – that’s not actually the case. The actual true distinction is that:

Direct Memory is memory allocated under the traditional video game model, so the game controls all aspects of its allocation.

Flexible Memory is memory managed by the PS4 OS on the game’s behalf, and allows games to use some very nice FreeBSD virtual memory functionality. However this memory is 100 percent the game’s memory, and is never used by the OS, and as it is the game’s memory it should be easy for every developer to use it.”

As previously mentioned, it’s unknown what the remaining RAM will be used for; Sony has never said how much RAM would be allocated for the OS, nor have they said if there are any other services that additional RAM could be allocated to.

Sony likely won’t have anything more to say on the matter until Gamescom, if at all. If anything’s for sure, though, it’s that developers will be picking apart the PlayStation 4 to see what’s really going on under the hood once the console launches late this year.