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Comment by PhaseLockk | Hacker News Reader

FPGAs are a useful means of accelerating any algorithm where you want more performance than you would get from executing it on a CPU, but can't afford to create your own ASIC because the volume is relatively low. For example, it may be used in DSP applications for things like radar. This use as a reprogrammable accelerator is also why Amazon has introduced instances with on-board FPGAs to AWS.

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Also worth noting that for real time control you can't beat the speed. Essentially, everything you do on an FPGA happens at the same time. You could see a 1000 line Verilog file that completes a huge operation in a handful of cycles.

Also note that "speed" includes latency, and not just low latency but also deterministic. You can do things like adjust a timestamp or tweak a control equation knowing that a sample has been delayed through an N-stage pipeline/filter that advances at M hertz.

Yea, I misspoke there. %s/speed/latency/

Certain industries (esp nuclear) really like them because they can "prove" the set of attainable states in the FPGA.

Exactly.

There is an algorithm for detecting bursts of unusual activity which is extremely well suited for FPGAs: http://www.cs.nyu.edu/cs/faculty/shasha/papers/burst.d/burst...

Basically it is a tree of registers with checks. It can compute burst position and duration in the O(log(window size)) time (clocks). You look here at 2.5..5ns (200MHz..400MHz) multiplied by log2(window size) - 25..50 ns for window with 1024 samples. You just cannot get that kind of connectivity with CPU/GPU. Processing these samples in CPU will get you into several hundreds of ns, if not more.

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