PS3 and its OS | PS3Blog.net
The PS3, unlike the PS2 before it, has a real operating system running at the same time as the game. This operating system will take care of things like voice chat, video chat, instant messaging, and other stuff. I’d previously heard that the OS reserves one of the Cell’s seven SPEs to itself.
According to some “inside sources” (or something like that), PS3 Portal has uncovered that there’s a lot more to the picture. Supposedly the OS can request a second SPE of the currently running game at any given moment. Which means that a game can use the main PPU, plus 5 SPEs, no problem. It can use a sixth SPE knowing that it can be taken away at an instant’s notice. This isn’t so bad really. The PPU is a powerful core. Each SPE is a powerful core too. A game running on one PPU and 5 SPEs still has a lot of horsepower available to it. If that was all, the news wouldn’t be so bad.
But according to PS3 Portal’s sources, that’s not all. The OS also reserves 32MB of the GDR3 graphics memory and 64MB of the XDR main memory. That’s about 19% of the system’s memory. That’s a lot. In the world of console gaming, memory is as precious as Coca-Cola is to a programmer. And to pour 19% off a full glass isn’t so bad if there’s Coke in the glass, but its a major hindrance if it’s memory.
Well, it’s a rumour right now. And if there’s a hint of truth to it, maybe the numbers aren’t so bad. But either way, I have a feeling that developers can make up for that missing 19% and still make some killer games.