For some testing and benchmark purposes, a ratchet is better suited than an average.
https://golang.org/cl/67870053/ bumps up the number of AllocsPerRun runs of an
http test to avoid flakiness. This test would be more reliable using a lower number of
runs if it could measure the best run rather than the average. In addition, it could set
an explicit (rather than comparative) goal for the number of allocs, which would allow
it to catch other regressions. With care, MinAllocsPerRun could even use heuristics to
avoid requiring the user to pass an explicit number of runs.
For benchmarking tightly CPU-bound code with minimal scheduler/OS interactions, a
ratcheting benchmark will often yield more stable, useful results than an averaging
benchmark.
