PS3 memory (lack of)

[kencanvey]

I don't know if this has been suggested for the PS3, but I was wondering if something like ready boost on Vista could be used on yellowdog, plug in a 4gig usb drive and away ya go.
I am not a coder myself, but I thought it could overcome the lack of meaningfull memory?

Ken

Edit : sorry just noticed the PS3 dedicated forum

[Zion]

Would help a bit but not a huge deal.

Best thing to happen to PS3 Linux would be if Sony gave us access to the full 512mb of system ram instead of the miserable 208/228mb they allow us to use.

I firmly believe that one day Linux on the PS3 will be more than just a novelty and be more comparable to a desktop PC.

[ppietro]

Would help a bit but not a huge deal.

Best thing to happen to PS3 Linux would be if Sony gave us access to the full 512mb of system ram instead of the miserable 208/228mb they allow us to use.

I firmly believe that one day Linux on the PS3 will be more than just a novelty and be more comparable to a desktop PC.

Unfortunately, that would be difficult.

The PS3 is split into two separate memory systems. The PS3 has 256 Meg of RAMBUS XDR DRAM for the Cell as system memory - the RSX has 256 megs of GDDR3 DRAM as video memory.

There is a way to get the bridge chips to transfer traffic between the two memory "pools", but it might even be asymetrical - I think the RSX can access system memory at a higher speed than the Cell can access video memory. (Can't remember for sure, though.)

(Part of the spec. is here and here)

I remember reading something about this in an interview with a PS3 developer. He was mentioning that the 256 megs of graphics memory weren't exactly a hard limit for textures because he could access some of the system memory via the bridge.

(Note - I can't remember the exact term for the video memory - Sony has a phrase for it. Can't remember where I found that interview either. )

So - yeah - it's possible - but I don't think it's trivial. It's not like Sony said "You're only getting 256 Megs - bwa ha ha!". It would take a pretty major change to get the Cell to talk to the video ram and use it as system memory.

Cheers,
Paul

[javayoda]

Could someone buy the PS3 development kit and write a "virtualized" Linux that runs in the game os? Such a beast could access video memory.

I suppose if Sony can control the distribution of Game OS content, this could never happen. Interesting idea though.

[ppietro]

Could someone buy the PS3 development kit and write a "virtualized" Linux that runs in the game os? Such a beast could access video memory.

I suppose if Sony can control the distribution of Game OS content, this could never happen. Interesting idea though.

Theoretically, you could.

BUT (you knew this was coming..)

there's some issues.

First, you'd have to re-work Linux quite a bit. One of the "benefits" the hypervisor gives you is a standard PC/Mac architecture. It abstracts the PS3's inherent weirdness to present a standard "fake" computer. That's why PS3 Linux can be so rapidly developed.

By comparison, PS2 Linux didn't abstract. It took forever for changes and fixes to happen, since you had to work directly against the PS2 architecture, which was pretty complex. There were never any updates to the original PS2 Linux - different variations, but all from the same base libraries. I managed to compile a newer Linux kernel that was developed for a PS2 Broadband Navigator (in Japan!) from publically available sources - but it broke a few graphics libraries.

Second - as you mentioned - Sony controls the distribution of PS3 software. With the current model, you'd have to encrypt your code with their libraries to have it run on consumer PS3s. I don't think anyone has figured out a way to run unsigned code yet.

Still - an interesting thought.

Cheers,
Paul