PlayStation 4 Developers Have Access to 5.5 GB of RAM - Report
Remaining RAM dedicated to OS and other requirements.
UPDATE: Sony has issued a statement to Eurogamer on the memory report.
"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 vidoe 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."
It seems that based on this information 5 GB of RAM are available to developers. It also seems that this amount is static and not dictated by OS requirements which should make it easier for developers to work with.
ORIGINAL STORY: A new Digital Foundry report on the PS4 claims that developers using the system have access to at least 4.5 GB of data with 1 GB of "flexible memory".
The remaining 2.5 GB of the system's 8 GB of RAM is dedicated to the operating system and other requirements and will not be available to developers according to the report.
Digital Foundry states "Sony's internal docs say that 4.5 GB is the baseline amount of guaranteed memory available for game-makers and most likely what the lion's share of launch title will be using. However, other sources close to Sony indicate that developers can request up to an additional gigabyte of 'flexible memory', and use it to boost elements of the game - but only if the background OS can spare it."
Apparently this extra GB is difficult to incorporate and initially at least only Sony first-party studios will target its usage.
"Current PlayStation 4 dev kits have a 'Game Memory Budget Mode' in the debug setting featuring two options: normal and large. The normal mode setting confirms that 4.5 GB of memory is usuable for game applications," Digital Foundry continues. "The large mode increases this considerably to 5.25 GB, but the docs are clear that the extra RAM here is only available for application development, presumably in order to house debugging data. From what we understand, the extra gig of flexible memory appears to work in addition to these allowances."
Previous documents leaked from Sony had suggested that only 512 MB of data was dedicated to OS requirements but this appears to have changed since the company opted to include 8GB of RAM in the PS4 - originally it was supposed to have only 4 GB. The 3 GB or so allocation for OS requirements brings the PS4 in line with the Xbox One's RAM setup.
However, it appears that when the OS and other system features are finalised Sony may be able to reduce the amount of RAM dedicated to these features allowing developers more room on PS4. It does not appear to be the case that Microsoft will be able to follow suite with Xbox One due to the way in which that system has been constructed..
It's worth noting that Sony's R&D team has reduced the OS memory requirement on the PS3 over time.
Sony has not yet commented on the report.