On Thu, Mar 16, 2023 at 12:51 AM Bastian Germann <bage@xxxxxxxxxxxxx> wrote: > > Am 15.03.23 um 15:18 schrieb Masahiro Yamada: > > "dpkb-buildpackage -j<N>" sets not only DEB_BUILD_OPTIONS > > but also MAKEFLAGS. > > > > > > This is clearly explained in "man dpkb-buildpackage". > > > > > > -j, --jobs[=jobs|auto] > > ... > > Will add itself to the MAKEFLAGS environment variable, which should > > cause all subsequent make invocations to inherit the option, thus > > forcing the parallel setting on the packaging ... > > I see. The testing/unstable dpkg-buildpackage version changed the -j behaviour. > -j only sets DEB_BUILD_OPTIONS=parallel= now. > > The man page now says: > > --jobs-force[=jobs|auto] > This option (since dpkg 1.21.10) is equivalent to the --jobs option except that > it will enable forced parallel mode, by adding the make -j option with the computed > number of parallel jobs to the MAKEFLAGS environment variable. > > > Your statement sounds like > > > > 'MAKEFLAGS=-j<N> dpkg-buildpackage' > > > > is the only way to build packages in parallel. > > It is in v1.21.10 or later (or using --jobs-force which does the same thing). > > > Apparently, dpkg-buildpackage provides a much shorter way > > and invokes internal Make in parallel. > > > > > > > > > >> > >> So it is not used to run the actual build, just the top level `make -f debian/rules` invocation. > >> You can set --jobs-force=16, which ends up in MAKEFLAGS but the point of the patch is that one can use > >> the usual way of parallelizing. > > > > > > What is the "usual" way in this context? > > The usual way is dpkg-buildpackage -jN but that does not work with later versions. > > > Do you mean > > 'DEB_BUILD_OPTIONS=parallel=16 dpkg-buildpackage -b' > > is the usual way for parallel building? > > > > If so, I agree. This patch caters to this case. > > > > > > But, I think your code should go to debian/rules > > instead of scripts/package/deb-build-option. > > Kbuild's "make clean" works much faster with the parallel option. > > > > > > Also, the commit description should explain the > > benefit of this patch. > > I will clarify the dpkg-buildpackage behaviour change and will move the stuff to debian/rules > in v2. Please do so. Now I understand the point of this patch. Indeed, my dpkg-buildpackage is old. (v1.21.1 on Ubuntu 22.04) Thanks. -- Best Regards Masahiro Yamada
