Oddly bad performance

[s-h-a-d-o-w]

OS: Win7 x64

wmi-client x 6.75 ops/sec ±3.90% (36 runs sampled)
process-list x 9.97 ops/sec ±2.53% (51 runs sampled)
ps-node x 0.07 ops/sec ±1.18% (5 runs sampled)

Benchmark setup, see: https://gist.github.com/s-h-a-d-o-w/c0b7ee374db044a21a6b5b1e99d269f0

Something can't be right here, considering that ps-node uses wmic internally. So the result should at least be somewhat similar to using wmic a bit more directly via wmi-client.