On Mon, Jun 18, 2018 at 06:52:18PM +0200, Nicolas George wrote: > Tomas Härdin (2018-06-18): > > Others have mentioned this already, but it bears repeating: the build > > (make) isn't what's so slow, configure is. I went ahead and did some > > profiling on it based on the StackOverflow thread that pops up when one > > Web-searches "bash profiling" [1]. I went with what the second guy in > > there says, because the first method eventually invokes the OOM killer. > > Before that, I suspect it would have been interesting to test a > configure from two years ago, and bissecting if it happens to be much > faster.
The speed of configure declined very significantly over time, here are some quick tests, not full bisects: but theres another point which i have not seen anyone make but maybe i missed it. If changes which decrease speed go in unhindered and without correction then no system, not a custom one, no meson no autotools, no cmake is guranteed to prevent such speed decline. Of course some of the decline will be due to added features and the added tests they need. also the speed seems worse with bash so anyone wanting a quick fix, do not use bash for configure. (note /bin/sh is dash here on my ubuntu box, and that is used by default i think) master: bash ./configure ; time bash ./configure real 0m56.345s user 0m43.532s sys 0m15.668s ./configure ; time ./configure real 0m15.788s user 0m8.469s sys 0m9.677s dash ./configure --cc='ccache gcc' --tempprefix=/home/michael/fftmpconf ; time dash ./configure --cc='ccache gcc' --tempprefix=/home/michael/fftmpconf real 0m13.982s user 0m7.591s sys 0m8.693s release/4.0: bash ./configure ; time bash ./configure real 0m56.337s user 0m43.207s sys 0m15.988s ./configure ; time ./configure real 0m15.704s user 0m8.352s sys 0m9.713s dash ./configure --cc='ccache gcc' --tempprefix=/home/michael/fftmpconf ; time dash ./configure --cc='ccache gcc' --tempprefix=/home/michael/fftmpconf real 0m13.966s user 0m7.414s sys 0m8.877s release/3.4: bash ./configure ; time bash ./configure real 0m21.324s user 0m18.041s sys 0m3.693s ./configure ; time ./configure real 0m6.756s user 0m4.158s sys 0m2.822s dash ./configure --cc='ccache gcc' --tempprefix=/home/michael/fftmpconf ; time dash ./configure --cc='ccache gcc' --tempprefix=/home/michael/fftmpconf real 0m4.849s user 0m2.887s sys 0m2.148s release/3.0: bash ./configure ; time bash ./configure real 0m16.955s user 0m13.770s sys 0m3.485s ./configure ; time ./configure real 0m6.006s user 0m3.616s sys 0m2.602s dash ./configure --cc='ccache gcc' --tempprefix=/home/michael/fftmpconf ; time dash ./configure --cc='ccache gcc' --tempprefix=/home/michael/fftmpconf real 0m4.269s user 0m2.401s sys 0m2.034s release/2.0: bash ./configure ; time bash ./configure real 0m11.050s user 0m8.855s sys 0m2.465s ./configure ; time ./configure real 0m4.443s user 0m2.622s sys 0m1.983s release/1.0: bash ./configure ; time bash ./configure real 0m14.104s user 0m10.045s sys 0m4.852s ./configure ; time ./configure real 0m4.712s user 0m2.250s sys 0m2.761s release/0.7: bash ./configure ; time bash ./configure real 0m9.441s user 0m6.607s sys 0m3.363s ./configure ; time ./configure real 0m3.346s user 0m1.583s sys 0m1.960s release/0.6: bash ./configure ; time bash ./configure real 0m5.679s user 0m3.431s sys 0m2.674s ./configure ; time ./configure real 0m2.670s user 0m1.276s sys 0m1.556s release/0.5: bash ./configure ; time bash ./configure real 0m5.107s user 0m3.310s sys 0m2.076s ./configure ; time ./configure real 0m1.949s user 0m0.893s sys 0m1.190s [...] -- Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB Breaking DRM is a little like attempting to break through a door even though the window is wide open and the only thing in the house is a bunch of things you dont want and which you would get tomorrow for free anyway
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