Caseless virtualization cluster: one machine is 43% faster than the others

Edit: Mystery solved — see the end

The hosts are identical — motherboards, memory, processors — yet one machine is 43% faster than the others, consistently, on a simple compile benchmark with everything on a ramdisk.

dmidecode and cpuinfo data is here. That should cover all questions about the hardware and processor configuration, I think.

Kernels are identical (all 3.11.10-301.fc20.x86_64).

I’ve no idea, but I’m starting to doubt my own sanity now!

Edit: Mystery solved:

It turned out to be a difference in the OCaml compiler versions installed. On the “fast” machine I had installed the new compiler, which it turns out is quite a bit faster.