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First-Gen Xbox 360 Games Single-Threaded?
Scott Gualco wrote to mention a report at The Inquirer indicating that, despite the 360 itself being capable of multi-threading, first generation 360 titles will be single-threaded. From the article: "Every new machine has a nasty first set of games as the programmers work up to speed on the hardware. In this case, the up side is that there is about 6x the CPU power available and coming to a console near you in the second generation of games. The scary part is that everyone tells me that the PS3 is harder to program for than the Xbox360, and the tools are nowhere near the quality of Microsoft's. That means that even with an extra six months of design time, the initial PS3 games may be worse." Commentary available at Joystiq.
first generation 360 titles will be single-threaded ... the initial PS3 games may be worse
They'll be half-threaded?
If I have been able to see further than others, it is because I bought a pair of binoculars.
Of course it's not true.
In case it's hard to work out, here's an alternative (and, I suspect, wholly correct explanation):
You've had real 360 dev kits for not very long - you've had to limp along with some half-way house that probably emulates many things until then. Your game is a launch title. This means it has a hard deadline. Either you launch when the Xbox launches, or you don't. This is a pretty binary state of affairs.
You're under intense time pressure. Most of the tools you're using are new/revised, and you have to create assets that are a different level of detail/effort than the previous games you've made, so you need to learn a lot of new tricks again. While you're updating the game engine itself, of course. Everything's changing.
Now, do you want to add to this volatile mix a bunch of multi-threading stuff for core game mechanics, with all the new code/mechanisms this will entail, and issues produced by multi-threaded access to game data, sync issues, race conditions, etc. and jeopardise the launch date of the game?
Or do you want to do the best you can in the time you have available?
I know which I'd choose.
(Aside: I see a lot of comments about audio, etc - of course multi-threading for stuff like audio playback is a no-brainer. Trust me, that's not the sort of thing that game devs are talking about when they say multi-threading games is hard. Conversely, multi-threading audio playback is not exactly a huge win anyway. The chipsets on these consoles do all the hard stuff - all the audio playback engine is doing is filling buffers and updating playback parameters. Exactly how long do you think that takes anyway?)
Unlike the other reply, I do disagree with John Carmack. I don't think he really knows what he's talking about in this case. The Xbox 360 is based on multiple (mostly) symmetric general purpose cores, whereas the PS3 is based on having a single general purpose core and multiple DSPs. This is a huge difference!
The DSPs on the PS3 are much, much faster than the PPC core, and your code will run faster even if you just farm a task to a DSP and wait for it to finish (i.e not parallel). They are harder to program than the PPC core, but hey that's what Devkits and proper code design were invented for. Probably the majority of your team doesn't need to know how to program it - they just call the appropriate API function like "BlendSpanLine" or "CopyBuffer" a couple of experts (or Sony) wrote for them.
I think when Carmack commented on the state of parallelism in consoles, he didn't quite grasp how different the approach is on the PS3 and how much better a solution it actually is. Sony and friends correctly identified that (I'll hand-wave here) 90% of processing is taken up in 5% of your code, and that 5% is generally a tiny little loop you can hand optimise and shove on a DSP. I mean, FFS this is exactly what we're doing on PCs using the shader engines on graphics cards! Why complain when the PS3 offers the same thing but more versatile and more parallel?