bug#71094: [PATCH] Prefer to run find and grep in parallel in rgrep

[Manuel Giraud]

Eli Zaretskii <eliz@gnu.org> writes:

[...]

>> >> So here is another example: a Linux kernel checkout (76K files). Also
>> >> about 30% improvement: 1.40s vs 2.00s.
>> > 
>> > This is all highly system-dependent.
>> 
>> Naturally. So it'd be great to see some additional data points from 
>> users on other systems.
>> 
>> Especially those where the default limit is lower than it is on mine.
>
> I'd be happy if someone could time these methods on MS-Windows and on
> some *BSD system, at least.  Bonus points for macOS.

I'm not sure it is what you asked for but here is some numbers on
OpenBSD (native 'find' and 'xargs'):

$ time find ~/emacs-repo -type f -exec grep foo {} + > /dev/null
    0m04.09s real     0m03.29s user     0m00.74s system
$ time find ~/emacs-repo -type f -print0 | xargs -0 grep foo > /dev/null
    0m04.10s real     0m03.45s user     0m00.66s system    

$ find /usr/src -type f | wc -l
  114315
$ time find /usr/src -type f -exec grep foo {} + > /dev/null
    0m14.07s real     0m07.68s user     0m06.29s system
$ time find /usr/src -type f -print0 | xargs -0 grep foo > /dev/null
    0m13.83s real     0m07.94s user     0m06.25s system
-- 
Manuel Giraud