Re: [PATCH v3 24/34] t/perf/p7519: speed up test using "test-tool touch"

>
> Elijah Newren <newren@gmail.com> writes:
>
> > On Tue, Jul 13, 2021 at 10:10 AM Jeff Hostetler <git@jeffhostetler.com> wrote:
> >>
> >> a quick test on my Windows machine shows that
> >>
> >>         test_seq 1 10000 | xargs touch
> >>
> >> takes 3.1 seconds.
> >>
> >> just a simple
> >>
> >>         test_seq 1 10000 >/dev/null
> >>
> >> take 0.2 seconds.
> >>
> >> using my test-tool helper cuts that time in half.
> >
> > Yeah, test_seq is pretty bad; it's just a loop in shell.  Is there a
> > 'seq' on windows, and does using it instead of test_seq make things
> > faster with Ævar's suggested command?
>
> Unless I am misreading Jeff's message, I do not think that makes
> sense.  Counting to 10000 in shell loop is trivial (0.2 seconds),
> but letting touch invoked 10000 times to create (or smudge mtime of,
> but I suspect that is not what is going on here) 10000 files takes
> 3.1 seconds, and of course a native binary that creates 10000 files
> with a single invocation would be faster.
>
> > I'd really like to modify test_seq to use seq when it's available and
> > fall back to the looping-in-shell when we need to for various
> > platforms.
>
> So, if I am reading Jeff correctly, that optimizes something that is
> not a bottleneck.