Fix profile feedback with -jN and add profile-fast

Profile feedback always failed for me with -jN. The problem
was that there was no implicit ordering between the profile generate
stage and the profile use stage. So some objects in the later stage
would be linked with profile generate objects, and fail due
to the missing -lgcov.

This adds a new profile target that implicitely enforces the
correct ordering by using submakes. Plus a profile-install target
to also install. This is also nicer to type that PROFILE=...

Plus I always run the performance test suite now for the full
profile run.

In addition I also added a profile-fast / profile-fast-install
target the only runs the performance test suite instead of the
whole test suite. This significantly speeds up the profile build,
which was totally dominated by test suite run time. However
it may have less coverage of course.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Andi Kleen 2014-07-07 23:35:11 -07:00 коммит произвёл Junio C Hamano
Родитель 5d7fd6d06f
Коммит 066dd2632a
2 изменённых файлов: 29 добавлений и 6 удалений

14
INSTALL
Просмотреть файл

@ -28,7 +28,7 @@ set up install paths (via config.mak.autogen), so you can write instead
If you're willing to trade off (much) longer build time for a later
faster git you can also do a profile feedback build with
$ make prefix=/usr PROFILE=BUILD all
$ make prefix=/usr profile
# make prefix=/usr PROFILE=BUILD install
This will run the complete test suite as training workload and then
@ -36,10 +36,20 @@ rebuild git with the generated profile feedback. This results in a git
which is a few percent faster on CPU intensive workloads. This
may be a good tradeoff for distribution packagers.
Alternatively you can run profile feedback only with the git benchmark
suite. This runs significantly faster than the full test suite, but
has less coverage:
$ make prefix=/usr profile-fast
# make prefix=/usr PROFILE=BUILD install
Or if you just want to install a profile-optimized version of git into
your home directory, you could run:
$ make PROFILE=BUILD install
$ make profile-install
or
$ make profile-fast-install
As a caveat: a profile-optimized build takes a *lot* longer since the
git tree must be built twice, and in order for the profiling

Просмотреть файл

@ -1643,13 +1643,20 @@ SHELL = $(SHELL_PATH)
all:: shell_compatibility_test
ifeq "$(PROFILE)" "BUILD"
ifeq ($(filter all,$(MAKECMDGOALS)),all)
all:: profile-clean
all:: profile
endif
profile:: profile-clean
$(MAKE) PROFILE=GEN all
$(MAKE) PROFILE=GEN -j1 test
$(MAKE) PROFILE=GEN -j1 perf
endif
endif
$(MAKE) PROFILE=USE all
profile-fast: profile-clean
$(MAKE) PROFILE=GEN all
$(MAKE) PROFILE=GEN -j1 perf
$(MAKE) PROFILE=USE all
all:: $(ALL_PROGRAMS) $(SCRIPT_LIB) $(BUILT_INS) $(OTHER_PROGRAMS) GIT-BUILD-OPTIONS
ifneq (,$X)
@ -2336,6 +2343,12 @@ mergetools_instdir_SQ = $(subst ','\'',$(mergetools_instdir))
install_bindir_programs := $(patsubst %,%$X,$(BINDIR_PROGRAMS_NEED_X)) $(BINDIR_PROGRAMS_NO_X)
profile-install: profile
$(MAKE) install
profile-fast-install: profile-fast
$(MAKE) install
install: all
$(INSTALL) -d -m 755 '$(DESTDIR_SQ)$(bindir_SQ)'
$(INSTALL) -d -m 755 '$(DESTDIR_SQ)$(gitexec_instdir_SQ)'