
A Look at Altera's OpenCL SDK for FPGAs - luu
http://www.anandtech.com/show/7334/a-look-at-alteras-opencl-sdk-for-fpgas
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CthulhuOvermind
Interesting to see this here. I did my masters thesis on this sdk the past
September. We compared a neural network in native C to a CPU opencl
implementation, and a FPGA implementation. The FPGA had about 8-10 times the
kernel performance of a i7-2600k for the task. Interesting enough, what caused
the jump in performance was the capability to have memory close to the kernel,
with enough capacity to handle the kernel demands. The CPU was capped on what
the ram-cpu bandwidth was, around 21gigs, however, the slower pci-e FPGA did
not suffer, because of FPGA implemented memory could hold the necessary data
at hand. Hence I sent the data to the kernel asynchronously, then a kernel
with around 120 parallel implementations would operate and feed back the data
through pci-e.

Having OpenCl certainly reduced dev time by around 85% id say. And that's from
someone fluent with verilog, who didn't know openCL before doing this.

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minthd
How efficiently OpenCl used the FPGA ?

And BTW, i remember reading some paper that compared CPU/GPU/FPGA. The
conclusion was - GPU's win on compute/$, FPGA's win on compute/watt. Hard to
find the paper now, though.

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manis404
>How efficiently OpenCl used the FPGA ?

There will always be some inefficiencies introduced when comparing OpenCL to
Verilog. Hopefully, this will decrease in the future versions of OpenCL.
Notice that the development time decreased by over 80%...

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aylons
Lots of interest about FPGA in HN lately. I wonder what caused this spark.

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mmastrac
IMO: FPGAs are an interesting beast because they've been inaccessible to a lot
of people thanks to the poor and/or expensive tooling and development boards.

That's starting to change slowly and people are getting interested in trying
something new.

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aylons
Well, good development boards are cheaper nowadays, Vivado is slightly better
than ISE, but pro tools are still very expensive and, of course, terrible.

Actually, most discussions here in HN are about how bad FPGA tools are.

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be5invis
Seriously, I am using it to create an open-source quantum mechanics software,
supports both GPU and FPGA acceleration.

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PascLeRasc
Report back here when you do, please.

