I have the possibility of getting my hands on a practically unlimited supply of S905X2 Android boxes, they have 2GB of RAM and 8GB eMMC, only 100Mbit LAN but USB-3 as well.
I was joking around with colleagues, what about making an ARM cluster out of them? Use the 100Mbps port as a management port and add a USB3 Gigabit or 2.5G adapter for general traffic. Power the cluster by PoE using PoE to 5v splitters from a smart, management switch with PoE (10W each box?).
Lets say I got 40 boxes with 4 cores, that’s 160 cores and 80GB of RAM. It could run Armbian with Kubernetes or something lighter. I personally have no use for it, but it could be a fun proof of concept?
Tell me why I shouldn’t do this! Tell me why it won’t work and why I’d be wasting my time.
I think this mainly depends on your workloads. As others have stated, the CPU isn’t all that fast RAM is even tighter.
Remember, it doesn’t matter how much ram you have in total, if your individual nodes don’t have enough resources for your most demanding workload, it can’t run.
It could be interesting at least to see if these ARM devices of yours could be used as the control plane for K8S.
Again, RAM would be tight, but they could handle a small cluster I think. The only question would be whether the emmc is fast enough for etcd, but you can test that with fio.
I would play around with it. The worst thing that can happen is you gain experience with k8s and learn that those devices aren’t really suitable.