Lucas Nussbaum wrote: > On 29/01/08 at 17:23 -0300, Felipe Sateler wrote: >> Recently dpkg-buildpackage got the option to build in parallel via the -j >> option. This means that debian/rules is called with that option set, and sets >> parallel=n in DEB_BUILD_OPTIONS. >> The problem is that for build systems not using make (eg, scons), this option >> is not inherited. Of course, one could parse DEB_BUILD_OPTIONS and find if >> parallel=n is set and then call the build system with the equivalent option. >> However this means that, although one specified n threads of execution, there >> can be more than n threads concurrently. Consider this case: >> >> build: build-indep build-arch >> build-arch: >> scons -j$(NTHREADS) buildProgram >> build-indep: >> scons -j$(NTHREADS) buildDocumentation >> >> Where NTHREADS is calculated from DEB_BUILD_OPTIONS. If I call >> dpkg-buildpackage with -j2, I will get build-arch and build-indep running >> concurrently, which means I will actually get 4 scons threads running instead >> of the intended 2. >> >> What should I do? I see 3 options: >> 1- Don't use the -j flag in scons >> 2- Use the -j flag and potentially use more threads than specified >> 3- Use the -j flag with a lower number (eg, NTHREADS/2). >> >> Any opinions? > > Don't use dpkg-buildpackage -j. Only set DEB_BUILD_OPTIONS="parallel=n", > so build-arch and build-indep are not run in parallel, but you still get > several scons threads.
OK. But it makes me wonder what is the real use for -j in dpkg-buildpackage, then. -- Felipe Sateler -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
