On Jan 12, 2011, at 2:56 PM, Moeller wrote:
The "very large FIR filters" was a thought, as an example of an operation that
might benefit from a GPU at least when using OpenCL (or CUDA). I haven't done testing yet to
know if a GPU can do better than a CPU using vector instructions ... but I'm getting there.
If/when I do get there, I'll post my results& thoughts.
Very large FFT filters is also something worth looking into. GPUs have
been considered for real-time coherent de-dispersion of radio astronomy
data streams for pulsar detection. De-dispersion over large
bandwidths at low frequencies requires ferociously-large FFT filters, but in
order to make this a viable proposition, you likely have to do the
detection and folding on the GPU as well, producing an output data
stream that is several orders of magnitude smaller/slower than the
input stream. I read a paper on this, (for the specific case of
pulsar detection with real-time coherent de-dispersion), and they
concluded that it's doable, on the higher end GPUs, provided that
you do detection and folding on the GPU as well, otherwise you lose
due to transfer overhead.
It seems like the only time you ever really "win" with a GPU-based
solution is when you have to suck in large amounts of data,
pound on it furiously, and then produce an output stream that's
relatively modest. Otherwise, you seem to lose due to data-transfer
overhead.
--
Marcus Leech
Principal Investigator
Shirleys Bay Radio Astronomy Consortium
http://www.sbrac.org
_______________________________________________
Discuss-gnuradio mailing list
Discuss-gnuradio@gnu.org
http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
