Re: [PATCH 2/8] Documentation/Makefile: conditionally include ../GIT-VERSION-FILE
- From
Junio C Hamano <gitster@pobox.com>
- Date
- Nov 5, 2020, 21:52 UTC
- Message-ID
- <xmqqy2jfh3nz.fsf@gitster.c.googlers.com>
- In-Reply-To
- <32b7e1dc-8cc3-2236-08b8-4d268bbf8c0b@ramsayjones.plus.com>
Ramsay Jones <ramsay@ramsayjones.plus.com> writes:
Show 28 quoted lines
> The 'clean' target is still noticeably slow on cygwin, despite the > substantial improvement made by the previous patch. For example, the > second invocation of 'make clean' below: > > $ make clean >/dev/null 2>&1 > $ make clean > ... > make[1]: Entering directory '/home/ramsay/git/Documentation' > make[2]: Entering directory '/home/ramsay/git' > make[2]: 'GIT-VERSION-FILE' is up to date. > make[2]: Leaving directory '/home/ramsay/git' > ... > $ > > has been timed at 12.364s on my laptop (on old core i5-4200M @ 2.50GHz, > 8GB RAM, 1TB HDD). > > Notice that the 'clean' target is making a nested call to the parent > Makefile to ensure that the GIT-VERSION-FILE is up-to-date (prior to > the previous patch, there would have been _two_ such invocations). > This is to ensure that the $(GIT_VERSION) make variable is set, once > that file had been included. However, the 'clean' target does not use > the $(GIT_VERSION) variable, so this is wasted effort. > > In order to eliminate such wasted effort, use the value of the internal > $(MAKECMDGOALS) variable to only '-include ../GIT-VERSION-FILE' when the > target is not 'clean'. (This drops the time down to 10.361s, on my laptop, > giving an improvement of 16.20%).
This obviously relies on the fact that none of our build products to be cleaned are named using $(GIT_VERSION)---in other words, if our cleaning rule contained
rm -f git-$(GIT_VERSION)-manual.html
this optimization would not work well.
Luckily, I think we use GIT_VERSION only to engrave version number in the resulting document, and it does not affect the name of the build product, so this change is safe, I think.
Show 19 quoted lines
> Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com> > --- > Documentation/Makefile | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/Documentation/Makefile b/Documentation/Makefile > index 652d57a1b6..5c680024eb 100644 > --- a/Documentation/Makefile > +++ b/Documentation/Makefile > @@ -272,7 +272,9 @@ install-html: html > ../GIT-VERSION-FILE: FORCE > $(QUIET_SUBDIR0)../ $(QUIET_SUBDIR1) GIT-VERSION-FILE > > +ifneq ($(MAKECMDGOALS),clean) > -include ../GIT-VERSION-FILE > +endif > > # > # Determine "include::" file references in asciidoc files.