document time functions in Counters.ml
commitc4e1628df20534705b1de947c881f55ac50df294
authorLucian Wischik <ljw@fb.com>
Wed, 21 Oct 2020 06:08:34 +0000 (20 23:08 -0700)
committerFacebook GitHub Bot <facebook-github-bot@users.noreply.github.com>
Wed, 21 Oct 2020 06:10:36 +0000 (20 23:10 -0700)
treef4db886b740a01c6411d08ad099d501c7efb0801
parentff29bd02949b61366d6808d83f8c0bf22a8fa562
document time functions in Counters.ml

Summary: It's really important to know the precise definition of what we're measuring! For instance, what is its definition in OS terms? what is its granularity? I don't think the ocaml docs give enough information. So I just dug through to see what they do.

Differential Revision: D24381565

fbshipit-source-id: 46aeae470fc61856f1dcc89f96257b7bbe31492d
hphp/hack/src/utils/counters.ml