On Fri, Dec 24, 2021 at 06:37:43PM +0100, Ævar Arnfjörð Bjarmason wrote:
> $ git -c hyperfine.hook.setup= hyperfine -L rev HEAD~1,HEAD~0 -s 'make -C Documentation man' 'make -C Documentation -j1 man'
> Benchmark 1: make -C Documentation -j1 man' in 'HEAD~1
> Time (mean ± σ): 121.7 ms ± 8.8 ms [User: 105.8 ms, System: 18.6 ms]
> Range (min … max): 112.8 ms … 148.4 ms 26 runs
>
> Benchmark 2: make -C Documentation -j1 man' in 'HEAD~0
> Time (mean ± σ): 97.5 ms ± 8.0 ms [User: 80.1 ms, System: 20.1 ms]
> Range (min … max): 89.8 ms … 111.8 ms 32 runs
>
> Summary
> 'make -C Documentation -j1 man' in 'HEAD~0' ran
> 1.25 ± 0.14 times faster than 'make -C Documentation -j1 man' in 'HEAD~1'
Nice speed-up. Though I am not sure I totally understand where it comes
from ;). Reading 30248886ce8 and the documentation on .SUFFIXES from
[1], I am still unclear. I guess removing the obsolete built-in suffix
rules gives make less work to do in general?
So long as we're not depending on any of these, this seems like a nice
little boost to me.
> diff --git a/shared.mak b/shared.mak
> index 29f0e69ecb9..155ac84f867 100644
> --- a/shared.mak
> +++ b/shared.mak
> @@ -9,6 +9,11 @@
> %:: s.%
> %:: SCCS/s.%
>
> +## Likewise delete default $(SUFFIXES). See:
> +##
> +## info make --index-search=.DELETE_ON_ERROR
> +.SUFFIXES:
Hmm. s/DELETE_ON_ERROR/SUFFIXES? Or perhaps I'm holding this whole thing
incorrectly:
~/s/git [nand] (ab/make-noop) $ info make --index-search=.DELETE_ON_ERROR
no index entries found for '.DELETE_ON_ERROR'
~/s/git [nand] (ab/make-noop) $ info make --index-search=.SUFFIXES
no index entries found for '.SUFFIXES'
Thanks,
Taylor
[1]: https://www.gnu.org/software/make/manual/html_node/Suffix-Rules.html
