Interesting article over at Ars Technica with speculation about what the new PhysX processor from Ageia looks like and a discussion of commodity processors, the Cell, GPUs, and how new silicon can break into the HPC market. A few excerpts…
What the PhysX might look like:
Based on things I’ve heard and on my reading of Codeplay’s whitepapers, I’m certain that the PhysX PPU consists of multiple identical cores (maybe with one or two unique cores, like Cell’s PPE, but probably not), and that each of those cores has its own local storage. In other words, PhysX almost certainly looks a lot like Cell, but with more cores, and probably more per-core local storage.
On getting into HPC with new silicon:
The problem you face is that you can’t just produce a chip specifically for the HPC market, because the chip has to be available in enough volume to keep the price down, and the HPC market just isn’t big enough for that yet.
…If you’re IBM or Ageia, then the way to get your multicore coprocessor chip into COTS clusters is clear: sell the chip in the gaming market first, because the gaming market has a unique combination of high volume and an insatiable appetite for parallelism.
Of course the GPU people already have volume licked. They have two other challenges. One is power: as we’ve talked about before, GPUs are power hungry. The other is rapid change in the way GPUs are programmed:
…a rapid pace of microarchitectural evolution that can spoil investments in hand-optimization.…A GPU maker will change almost anything about a design if it means a boost in frames-per-second on top games. These changes mean that if you get really invested in low-level hand optimizations, then you’d better plan to stick with that exact same GPU for the life of your cluster.