Sony has given developers access to the seventh core of the PlayStation 4 CPU. Previously, along with the eighth and final core, it was reserved for the console’s operating system. The core may still be partly responsible for other functions.
Sony has not officially announced the news, but it was revealed in the patch notes for an FMOD update. That’s the middleware that handles the audio in the PS4’s SDK. A Neogaf user, among others, noticed the line in the notes. It reads “Added FMOD_THREAD_CORE6 to allow access to the newly unlocked 7th core”, which leaves little room for interpretation. Sources from Eurogamer confirm the change, but remain anonymous because there is an nda for the sdk.
This does not mean that PlayStation 4 games already on the market will now use core number 7 and gain performance from it. Game developers must specifically write in their software code that the core must be used and in what way. Games that are already on the market can benefit from the core if developers decide to use the extra core through an update.
Although the seventh core is now available to game makers, it is not yet certain whether the core will also be available to them at all times. It may be that the seventh core is still responsible for secondary functions of the console, such as taking a screenshot. In that case, making use of such a function can therefore have an effect on the performance in a game. According to Eurogamer’s sources, this may indeed be the case.
The same was done with Microsoft’s Xbox One console in January of this year. The seventh of the eight cores was also made available there for developers, but there too the operating system can lay claim to the processing power of this processor core, for example for processing voice commands. Developers get a maximum of 80% of the CPU time of that core with the Xbox One.