Nemesis 1
Lifer
- Dec 30, 2006
- 11,366
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Feel free to correct me if I'm mistaken, but I don't think threads and core (thread parallelism) have anything to do with SSE (instruction parallelism) ...
I also agree : being quite familiar with ray tracing et al, I know for a fact that it's more often easy than not to extract instruction parallelism from already embarrassingly parallel computations, and it's quite feasible to strongly optimize critical sections of the code using SSE (given a little more work, it's even possible to keep the same source and switch between SSE and x87 using templates or ifdefs). It is thus a bit surprising that no effort have been made on that matter (or at least none made it to us mere mortals).
Just to be clear, I don't think nVIDIA (nor AEGIA for that matter) crippled anything ... They just don't have any motive to invest some time into something that's not their priority (CPU PhysX). That is what I don't understand, given how slow CPU PhysX is : developers would be more inclined to learn the PhysX API if they could benefit from acceptable performance on CPU (but again, maybe nVIDIA did some benchmarks and decided the performance gain was not worth the cost) ...
As for multi-threading, I didn't dig into the library, so I can't tell if it's almost free to implement with PhysX or if you have to struggle to make it happen. What I gathered from my readings is that some complain that multi-threading is not embedded in the engine (the library does not spawn threads on it's own). We developers all know how lazy we are ...
Finally, I do think the article is misleading, suggesting the code is *artificially* crippled ...
You have much to learn about people . They won't adderess AVX as its a threat to PX.
All you will here is how SSE isn't suited to this type of work. I not a programmer so I don't know . But code for SSE is probably easier than PX code .
This is a good question for the guys at Beyond 3D . Its a great place to get this info . But that forum has been invaded by want to bees . That just don't cut it.