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Comment by mozumder | Hacker News Reader

OK now how quickly can FPGAs be adapted to search through Postgres indexes?

Netezza, a data warehouse appliance which was built on PostgreSQL, uses FPGAs as the first step to process data as it is read from disk.

Netezza (acquired by IBM) has been doing this for many years.

I can't see how it would help - this kind of search involves almost no computation and a lot of memory/disk bandwidth.

People need to remember that FPGAs are not a magic bullet, especially not for throughput; they're better used for low-latency hardware interaction and things where you need cycle-deterministic behaviour.

Crypto is a far more interesting potential case.

And low power computation

Are you sure about that? FPGA MIPS/Watt tends to compare rather badly.

What precisely is an "instruction" in the MIPS/watt rate here, given the FPGA context?

He's right in the sense that an FPGA will use more power than a dedicated chip. The logic elements are fairly large when compared to the ones in an Intel CPU for example. FPGAs are good for when you know you will need to change a design on the regular like prototyping or when the design will have many updates. If you need it to be faster or you need more than a few hundred, going with an MPGA (depending on the use) might be cheaper. These don't allow change to the design as its baked into the chip but they use the same type of logic as FPGAs and require less power as the logic elements are smaller.

Only low power consumption in the sense that you get to run what you want because the chip is fully dedicated to a task. A microcontroller could draw less power doing the same task.

I beg to disagree.

One need error correction to fight disk/OS failures and compression to conserve bandwidth. Both tasks are highly specializable and good candidates for FPGA implementation.

Having tool like FPGA at your disposal makes you look at problems differently.

Quickest way is to use what's called a high-level synthesis tool that converts a high-level version of algorithm to hardware language. Synthagate, Handel-C, Catapult-C, Synflow's C-flow, C-to-Silicon... many tools claim to do it. Best to have someone with hardware background help, though.

Xilinx has started to offer, for free , such high-level language tool , as long as you use their lower end fpga's, for those interested in trying such tool.

Is it Vivado they're giving away? That would be pretty awesome given even a Spartan6 is quite powerful.

Yep vivado HLS.

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