It also looks like it already happened on 5.14, so I would be looking at commits between 5.13 and 5.14:
Linux-5.13.0-40-generic-x86_64-with-glibc2.29 c++ g++ (Ubuntu 9.4.0-1ubuntu1~20.04.1) 9.4.0 1.524 1.507 8.431 2.278 Linux-5.14.10-300.fc35.x86_64-x86_64-with-glibc2.34 c++ g++ (GCC) 11.3.1 20220421 (Red Hat 11.3.1-2) 1.800 1.707 8.785 2.633 Linux-5.15.0-27-generic-x86_64-with-glibc2.35 c++ g++ (Ubuntu 11.2.0-19ubuntu1) 11.2.0 1.728 1.713 8.406 2.266 more results: https://github.com/pepe78/python-performance -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1965451 Title: C++ performance got worse going from Ubuntu 20 to Ubuntu 21 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gcc-11/+bug/1965451/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs