Node Usage - GPU metrics

[niknoronha]

Could we get GPU stats added to the node usage metrics. similar to the CPU stats that have been added in 18.0?

[lahwaacz]

There is an open PR for this: #57

[martialblog]

I think this needs some refactoring due to the newly introduced -gpus-acct parameter.

I've been looking at it and not sure if the code should be in node.go, would make some sense, since all other per-Node data are there - however - it might be better to add it to gpus.go, since it gets activated with the -gpus-acct parameter.

Here some output from a multi node cluster:

sinfo -h -N -O "NodeList: ,Gres: ,GresUsed:"

gpu-01 gpu:tesla:4 gpu:tesla:4(IDX:0-3)
gpu-02 gpu:tesla:4 gpu:tesla:4(IDX:0-3)
gpu-03 gpu:tesla:4 gpu:tesla:4(IDX:0-3)
gpu-04 gpu:tesla:4 gpu:tesla:3(IDX:0,2-3)
gpu-05 gpu:tesla:4 gpu:tesla:0(IDX:N/A)
gpu-06 gpu:tesla:4 gpu:tesla:1(IDX:3)
gpu-07 gpu:tesla:4 gpu:tesla:2(IDX:1-2)
gpu-08 gpu:tesla:4 gpu:tesla:4(IDX:0-3)
cpu-01 (null) gpu:0
cpu-02 (null) gpu:0
cpu-03 (null) gpu:0
cpu-04 (null) gpu:0

Or maybe even a new node_gpus.go?