David Wang (dwang@RWTexpanded.com) on 8/2/05 wrote:
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>fastpathguru (fastpathguru@yahoo.com) on 8/2/05 wrote:
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>
>>Re: The Mystery of the Missing FLOPS, is it possible that it's solved by accounting
>>for the extra meat in the PPE? I didn't see that mentioned as a possibility.
>
>You need 68 flops per cycle to get 218 GFlops @ 3.2 GHz.
>
>It's easy to get 56 of those flops from 7 SPE's, using FMADD, but then you'd need
>12 flops per cycle out of the PPE to get to 68.
>
>Again, assume that you can crank 8 Flops per cycle out with FMADD, you still need
>4 flops per cycle. The PPE is multi-threaded, but the impression that I got from
>the IBM folks is that the scalar and vector FP units are actually shared so you
>really can't get more flops out of the PPE either. Regardless, even if the FP units
>aren't shared, you still can't get 4 flops per cycle out of the scalar side of thing.
>
>So no, the beefier PPE can't get to 12 flops per cycle even if it had independent scalar/vector FP units.

Why not ? See Gekko ;).

Also, PS2 was subsidized by SCEI, but PlayStation 2 Linux was realized and it helped SCEI too as I know of at least one good coders who joined SCE that started console development on PS2Linux: getting many more people familiar with CELL's architecture (PS2Linux was shipped with some documentation about EE and GS while keeping other parts like the IOP, the SPU2 and other parts hidden away to separate professional PlayStation 2 development from PS2Linux coding even though the DMA Controller, thanks to a library known as SPS2, is fully accessible) and get more people developing for it would be something that IMHO will pay off.