[jschwartzi]

Because someone who understood the available resources and the actual user needs performed an analysis and determined that this would be sufficient. Commodity hardware eliminates the need to spend a year or two engineering a custom board, dealing with vendor BSPs, etc. It also eliminates the FTE that would be required to support all this.

They could also have chosen to use a reference design from another manufacturer but it's basically like using RPi but 100x more expensive. There's a good case to be made that this is the most cost-effective design for what they're trying to accomplish.

[imtringued]

They could also just have bought 12 Epyc 64 core Servers to get equivalent performance assuming they are exclusively compute bound. If they are IO bound even just 3 nodes with 100gbit NICs would be enough to outperform the Raspberry Pi cluster.

If they really wanted to develop a competitive cluster they'd need at least a SoC with 4 A72 cores, 10gbit NIC, 8GB RAM, and a local 128GB SSD.

Edit: I misread the article it's not a cluster with 3000 raspberry pies. It's just 3000 cores. 3 Epyc Nodes are faster than this cluster.

[marci]

It's not necessary about speed, it's about how to write code that runs efficiently, concurrently and/or in parallel on that many nodes.

IIRC, that's kinda how ethernet came to be, ther were working on the computing world of the future at xerox PARK, they had to create clusters to emulate the cpu power that would be available in the coming years. Looking at the current trend, from phones to servers, they go from two cores to I-don't-have-enough-fingers-except-if-I-count-in-binary cores. A 3000 cores raspberypi cluster can be an emulation of the computing environemnt of tomorrow, not in term of raw power, but in term of distributed computing, and lead to unforseen invention as the ubiquitous ethernet.

[pero]

pretty sure it's just for its press releasibility but ok