investigate why BenchmarkConcurrent scales differently wrt GOMAXPROCS on linux/amd64 vs darwin/arm64
Inital measurements https://docs.google.com/spreadsheets/d/1YOP1D_ZhuR-ednQhTH6SSrCkcR5bOHzCDoQBZMXvyAw (master branch @ 2c0b2bda)
Inital measurements https://docs.google.com/spreadsheets/d/1YOP1D_ZhuR-ednQhTH6SSrCkcR5bOHzCDoQBZMXvyAw (master branch @ 2c0b2bda)