On Fri, Jun 17, 2022 at 9:34 PM Nathan Chancellor <nathan@xxxxxxxxxx> wrote: > > On Fri, Jun 17, 2022 at 07:50:58PM +0200, Sedat Dilek wrote: > > On Fri, Jun 17, 2022 at 6:32 PM Nick Desaulniers > > <ndesaulniers@xxxxxxxxxx> wrote: > > > > > > On Fri, Jun 17, 2022 at 3:35 AM Sedat Dilek <sedat.dilek@xxxxxxxxx> wrote: > > > > > > > > On Fri, Jun 17, 2022 at 12:53 AM Sedat Dilek <sedat.dilek@xxxxxxxxx> wrote: > > > > > > > > > > On Thu, Jun 16, 2022 at 4:09 PM Sedat Dilek <sedat.dilek@xxxxxxxxx> wrote: > > > > > > > > > > > > On Thu, Jun 16, 2022 at 12:45 PM Jiri Slaby <jslaby@xxxxxxx> wrote: > > > > > > > > > > > > > > Until the link-vmlinux.sh split (cf. the commit below), the linker was > > > > > > > run with jobserver set in MAKEFLAGS. After the split, the command in > > > > > > > Makefile.vmlinux_o is not prefixed by "+" anymore, so this information > > > > > > > is lost. > > > > > > > > > > > > > > Restore it as linkers working in parallel (esp. the LTO ones) make a use > > > > > > > of it. > > > > > > TBH, I agree with Masahiro. I didn't understand this comment "esp. the > > > LTO ones." Jiri, can you clarify what you mean here? > > > > > > > [ CC Nathan and Sami ] > > > > > > > > I re-checked as my build-time takes approx. 15mins more than usual > > > > with Linux v5.17. > > > > > > > > [ Perf - seconds time elapsed ] > > > > v5.17: approx. 12500 > > > > v5.19: approx. 13500 > > > > > > > > +1.000 secs = +16,67mins > > So roughly 7.5% increase if I did my math correctly? > > > > Does this patch make a difference? > > > https://lore.kernel.org/linux-kbuild/20220616195759.3214538-1-samitolvanen@xxxxxxxxxx/ > > > > > > > Running a new build... > > I did a quick benchmark with Fedora's clang 14.0.0 and I didn't see an > increase of that proportion with your configuration (only about 1%, > which I would expect would be within the noise for new drivers and > such): > > Benchmark 1: 5.17 > Time (abs ≡): 287.744 s [User: 23497.818 s, System: 4444.602 s] > > Benchmark 2: 5.19-rc2 > Time (abs ≡): 290.027 s [User: 24567.290 s, System: 4834.458 s] > > Summary > '5.17' ran > 1.01 times faster than '5.19-rc2' > > Not to say that there is not an issue but it might be more visible with > slower hardware. > @Nick Desaulniers I applied the patch. Seen from build-time not really measurable. Noticed some binary size reduction. @Nathan Chancellor Yeah, that I was thinking, too. This is due to the number of driver (and modules) increased. And of course the changes to kbuild-system. It's hard to compare. Surely, ancient CPU (10 years) plus HDD etc. -Sedat-
