Sony have issued a statement to Eurogamer, clarifying how much memory developers will have access to. Essentially, they’ve explained the differences between “flexible” and “direct” memory, with Eurogamer working out that there is likely 5GB available to developers with 4.5GB of conventional RAM and 512MB of the “flexible memory”.
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 per cent 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.
We have no comment to make on the amount of memory reserved by the system or what it is used for.
So, that’s 4.5GB of direct memory, which is purely allocated to the game and then, according to Eurogamer, the flexible memory is “virtual address space”, of which 512MB is used for “physical area”, leaving 512mb available.
I’ve just realised that Sony still haven’t said how much RAM is actually used by the OS. Funny that. Maybe “not too much” would be a suitable description.