From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Petazzoni Date: Fri, 7 Feb 2014 17:43:55 +0100 Subject: [Buildroot] Antw: build speedup possible? In-Reply-To: References: <52F49E9D.2020506@andin.de> <52F4AEC7020000460004A4EE@gwia2.rz.hs-offenburg.de> <20140207162934.01acfe5a@skate> Message-ID: <20140207174355.383b6bb3@skate> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: buildroot@busybox.net Dear Fabio Porcedda, On Fri, 7 Feb 2014 16:54:20 +0100, Fabio Porcedda wrote: > > And in practice, how do you achieve this? When building in parallel, > > how do you record the fact that the test for libfoo in package A > > configure script was run before or after the installation of libfoo in > > the global sysroot? It's not only about recording the order of the > > build of the package: it's knowing whether each specific test of a > > configure script was run before or after the corresponding library was > > installed in the global sysroot. > > Well i admit i haven't thought about that corner case, I don't know an > easy solution for that. IMO this is not a corner case, this is precisely the problem we have been pointing out since the beginning when mixing a global sysroot with top-level parallelization. > > I think we should really not minimize the support problem that > > parallelization without per-package sysroot is going to cause. > > My suggestion was based on the assumption that there is a way to > reproduce the exact build order. > But if that is not true i agree with you. I don't really see how to reproduce the exact build order, so the support problem will be here. That's really why I have been a bit skeptical and resistant to this patch series from the very beginning. I am obviously very interested in ways to reduce the build time. But doing that at the expense of reliability is not a good idea in my opinion, as users will face spurious failures that we will not be able to reproduce and fix. If we want to get this to the next level, someone need to experiment with per-package sysroot. Of course, this would be a long experiment, without necessarily at the end the guarantee that we will accept it, because it may be too complex to match Buildroot simplicity principle. Best regards, Thomas -- Thomas Petazzoni, CTO, Free Electrons Embedded Linux, Kernel and Android engineering http://free-electrons.com