Re: Time resolution in Emacs

[Eli Zaretskii]

> Date: Fri, 29 Apr 2022 22:19:10 +0700
> Cc: Eli Zaretskii <eliz@gnu.org>, emacs-devel@gnu.org
> From: Max Nikulin <manikulin@gmail.com>
> 
> >> As to 16ms resolution, at least for `benchmark-run' I would like to have 
> >> finer granularity.
> > 
> > Do you really run benchmarks that end in a matter of milliseconds?
> 
> It may be enough for quick estimations during comparison of methods 
> having order of magnitude difference in running time.

Ut usually produces skewed or random results, IME.

> Sometimes it is necessary to measure duration of particular calls 
> without repetition.

In which case one must arrange for repetitions that don't have the
effect of repetitions.

> > In any case, measuring a time interval with high precision doesn't
> > necessarily need a fine-granular wall clock.
> 
> My experience is that it is even less probable to find monotonic clock 
> or performance counters implemented when some legacy method is used for 
> wall time.

My experience is different.