Hi all,
On Tue, 24 Jun 2008, Sergei Pogrebenko wrote:
I also had some doscussions with Dan Werthimer about his FPGA plans
(in a wake of uniboard project) and about Sony PS3. He and his team
tried to re-write s...@home for PS3, but got it sadly running well below
expectation. They contacted Sony/IBM compiler guys, but for 3 month
no answer.
We fortunately have the answer.
Even vectorized and optimized code for PS3 often gets five to ten per cent
of the actual calculation capacity.
It's a bit tricky to get the (about) 90% we got, we took Daniel
Hackenberg's matmul program and modified it. Daniel actually got 97%
efficiency, we didn't bother about the last seven per cent. It's less
expensive to buy more playstations.
Cross-pol feature is also of interest in a wake of new (ATA-kind)
very broad band linear polarized feeds, so the conversion to circular
polarization has to be done. For that the cross-pol complex spectrum
should be calculated.
Our results are very in-line with FPGA spectrometers, although they
are much faster, it's difficult to get really hign resolution with them.
Well, the cell processors are the best you can have at the time, for some
of the tasks. FPGAs or display controllers are better for very limited
tasks, normal Intel-architecture or powerpc processors for very big.
If you have to do number-crunching the cell processor may be the best.
And for you casper people, the PS3 control program may be even better
platform than PS3 Linux although much trickier. The folding-at-home people
are the ones to ask, they have the experience.
Best regards,
Jouko
