On 08.01.26 12:37, Sam James wrote: > Frank Scheiner via Gcc <[email protected]> writes: > >> Hi all, >> >> as Tomas' ran into an OOM situation for the testsuite, I took over and >> bootstrapped gcc-16-20251214 on my rx2800 i2 in ca. mid December. >> Testsuite results are on [1]. I'll send a separate email for a possible >> discussion of these to the gcc list. >> >> [1]: https://gcc.gnu.org/pipermail/gcc-testresults/2025-December/865397.html >> >> As shown in the testsuite results, the build time increased to some >> degree compared to older runs. For bootstrap this took nearly an hour >> longer (375 mins) compared to GCC 15.2.0 (319 mins; unfortunately >> I don't have the timing data for GCC 15.1.0, which is directly from >> trunk IINM). >> >> Together with the testsuite run, we are now close to 13 hours for the >> whole process on a rx2800 i2 w/1 x Itanium 2 9320 (4 cores, 8 threads) >> with everything done in `/dev/shm`. >> >> Only languages C and C++ were made. I used Linux v6.19-rc1 for >> bootstrapping gcc-16-20251214 and v6.17-rc1 for GCC 15.2.0. I'm unsure >> if the build time increase could be due to the used kernel, but I'll >> also look if cross compilations on GHA and locally show a comparable >> build time difference. >> >> Still, I wonder, do other arches show a similar increase in bootstrap >> timings for gcc-16-[...] compared to GCC 15.x.x? > > Bootstraps on trunk will take longer by default because we enable more > assertions ("checking") for development, i.e. the default for releases > is --enable-checking=release, while for development, it is > --enable-checking=yes,extra. > > But I note that your test-results link has --enable-checking=release > which is curious, so that doesn't explain this.
There also were some reports about performance issues with Linux v6.19, tough for pre-rc1 according to the date, see for example [2]. [2]: https://www.phoronix.com/review/linux-619-sched-regress Not sure if this could have a play in this. I still need to check on the cross-bootstrap runtimes on GitHub ([3]). [3]: https://github.com/johnny-mnemonic/gcc-autobuilds/actions > You could maybe use bootstrap-time from > https://gcc.gnu.org/install/build.html but I admit I've never used it > and I don't know if it'll be useful (or not) for debugging this. That could be interesting! Maybe something for future builds. Thanks! Cheers, Frank
