Could we get GPGPU with RSX in the PS3?

[scificube]

I should rephrase the question...can we have a more GPGPU situation with RSX than is commonly accepted is more inline with what I'm trying to ask.

Looking at Xenos's Memexport capability it is the ability to write partially processed shader data to memory (rather than data from fully executed shaders) and to read the data back into shaders that allows for a more GPGPU in Xenos. At least this is what I understand.

I wonder if this is possible in the PS3 via a different mechanism. I realize at this point I am asking about something that is most likely an unknown so I'm going to frame this as an "if ______ could ______ work" kind of situation.

I was wondering if Cell could snatch partially processed shader data from RSX and pipe it back to the GPU could this allow for a kind of Cell assisted GPGPU situation. In this situation, Cell's role is not to handle processing the data but to control the data's movement...Cell exports and imports the shader generated data for RSX is what I'm trying to describe. This would be an interesting way of utilizing the large amount of bandwidth between Cell and RSX.

I would like to here the thoughts of the B3D crew as to what needs to be true for this to be possible and just how probable what needs to be there is actually there...or even if this is a good idea at all.

Please Discuss

 

[Titanio]

The answer to the first title's question is - yes, of course. Go check out gpgpu.org and see the work that's being done. Of perhaps more direct relevance to games, the first chip to run HavokFX was a G70 chip IIRC.

As to the question of alternates to memexport..the common approach to data input and output is via vertices, textures and render targets.

 

[scificube]

Thanks for the info. Titanio. I'll check the site out when I get some time.

I understand what you're saying about the standard...data structures? Storage structures...ok...well I get what you mean.

I was thinking Cell and RSX could communicate more directly but even still couldn't Cell store the data a in a texture and send it directly to RSX?

 

[Titanio]

Cell can store data in a texture and send it to RSX, yes - but whether you can send it directly, or have to go through memory, we don't know yet..(same question about vertices from cell to rsx).

 

[scificube]

It'd be nice to know these things...maybe we won't have to wait much longer...I hope not at least.

If it could do this I wonder if this would provide something close or as good as Xenos's Memexport capability...I wonder if such a thing is the X360 may actually be better if Xenon doesn't have to write to data to memory first like Xenos has to.

 

[PeterT]

IMHO (and I have some experience in this field) most of the tasks suitable to GPGPU processing can be done faster and more easily on Cell, so I very much doubt that you will see much of it on PS3.

 

[scificube]

There has been some debate about what can be done faster where around here. Is how you feel because of how powerful Cell is, how flexible Cell is or a combination of both? It sounds like you mean both but I'm asking to be sure.

I'm curious as to whether you feel the same about Xenon and Xenos. It would seem the situation is a little better for say tesselation even though the unit is fixed function, but I wonder about the other goodies like physics etc.