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Comment by im_down_w_otp | Hacker News Reader

I bought five of these to do some Erlang, Rust, and Pony-lang distributed systems programming and testing on. Lack of mainline kernel support is a bit annoying, but that's being fixed with Linux 4.6 (which is getting S905 support).

The only other issue I've run into is lack of RTC being a bit more trouble than I'd anticipated for some things. None of the stuff I'm building directly has any hard dependencies on linear time, because it wouldn't be much of a reliable or deterministic distributed system if it did ;-), but some underlying facilities that I depend on don't take very kindly to having their clocks reverted back in time on a regular basis.

Those minor foibles aside... these are exceptional SBC's and very, very competitively priced. I'd probably donate a kidney for a proper SATA port on them though. :-)

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Not sure if this is helpful, but you can get older, (but oddly still very powerful) xeon servers on Ebay for under $200. That's what I use for prototyping distributed systems. The advantage is the hardware architecture is the same you would use in a production system. I think maybe a lot of companies that maintain data centers are flooding the used market? For $250, I was able to configure 64gb RAM Xeon servers that clock in a little over 1/4 of the CPU speed of very high end brand new servers.

...not that I don't love Raspberry Pi, I considered using them, but prefer something where I won't run into compatibility issues for prototyping (and they have SATA ports).

Having five Xeon servers on your desk is not much fun when it comes to noise, but if you have some sort of server area yeah I agree you can get some good deals.

There's a ton of multi-node servers out there for dirt cheap. That way you only need one noisy server on your desk, or you can hide it away somewhere. I'm a fan of the c6100(ish) servers that have been getting offloaded on ebay lately:

http://www.ebay.com/itm/Dell-XS23-SC-Cloud-Server-4-node-8x-...

http://www.ebay.com/itm/Dell-C6100-C6105-Cloud-Server-6x-1-8...

Have you heard a C6100? I haven't, but have heard they're insanely loud.

I think most server machines are probably pretty loud. They're designed to go in data centers where noise is not a factor. They put a lot of components in a somewhat small space, then they put passive heatsinks on the CPUs and blow air through the whole case, including the passive heatsinks. The fans are really loud because they are both small and powerful.

If you wanted, you could take the top off the case and then put bigger, quieter fans in, or perhaps put larger, quieter active desktop heatsinks on just the CPUs. I think this would be okay, I don't think the rest of the motherboards usually require the fans, but I could be wrong.

Those are excellent, I think a way better deal than the price I got. The processors are 3/4 the power of the ones I configured (Xeon L5420 vs Xeon E5540) and have 24gb RAM per node for under $100 each. Its really shocking you can get machines that powerful for that little, they even come with power supplies. With the dual CPU, they are more powerful than a bunch of the i7's out there.

How did you find out about them? Just searching Ebay or is their a good resource to learn about these things? For the ones I got, I just stumbled upon them on Ebay.

Haha, yeah, these are in their own room. I can hook a monitor up to them if I need to, but I mostly just SSH into them from my office. The room is very loud and somewhat hot. Another drawback of having a cluster this size (15 machines) is the cost of electricity.

I just wanted to day thank you for posting this! I had no idea.

Can you plug them into a wall socket or do you need electrified rails?

The ones I got have their own power supplies, I don't have rails, so I was pretty careful about this.

I'm not totally sure about this, but I think even ones with rails, you can often take the adapter card off the motherboard that connects them to the rails and put in your own power supply. In practice, it would probably be way easier to buy something thats already configured to have a power supply instead of use rails for power, there are plenty out there.

Oh, the use of small footprint, low-power hardware is completely intentional in this case. :-)

I used to have a band amp rack w/ 5 infiniband connected machines for testing existing distributed systems. Then I decided that they're all doing it wrong.

What made you come to that conclusion? Is there better performance vs. hardware cost vs electricity cost with the raspberry pi? I've often wondered if the cost/benefit ratios will tip in the favor of really cheap parts as people get better and better at building systems that horizontally scale.

Great info, thanks!

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