On Sun, Apr 02, 2023 at 09:54:04PM +0200, Dan Čermák wrote: > The only benchmark that *I* am aware of is this one done by Martin > Jambor: https://jamborm.github.io/spec-2022-07-29-levels/ This is very … underwhelming. x86-64-v2 is essentially identical to x86-64-v1. x86-64-v3 is better. It even shows speed-ups of 20%, but only with -Ofast. And -Ofast is not something that can be enabled as a default build flag, because it leads to surprising and unpredictable behaviour in some cases. (*) At -O2, which we use, the speed up is maybe 10%. > tl;dr; v2 does not really bring notable improvements, only v3 but also > only in some selected synthetic benchmarks. > > openSUSE Tumbleweed went a different route and chose to utilize > glibc-hwcaps instead: > https://en.opensuse.org/openSUSE:X86-64-Architecture-Levels > https://lists.opensuse.org/archives/list/factory@xxxxxxxxxxxxxxxxxx/thread/ZOHLT4CQ7TDOJJ2VV7HKMN5G2MR2CTMD Yeah, I think that's the way to go. I think we should identify 100 shared libraries which would be positively impacted by x86-64-v3 and provide a -v3 subrpm for them. This would be a nice feature for F40. Zbyszek _______________________________________________ devel mailing list -- devel@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to devel-leave@xxxxxxxxxxxxxxxxxxxxxxx Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/devel@xxxxxxxxxxxxxxxxxxxxxxx Do not reply to spam, report it: https://pagure.io/fedora-infrastructure/new_issue
