Frantisek Zatloukal <fzatlouk@xxxxxxxxxx> writes: > On Wed, Jul 31, 2019 at 11:00 AM Kevin Kofler <kevin.kofler@xxxxxxxxx> > wrote: > >> * the performance increase to be had is marginal, given that we are mostly >> talking about code written in C or C++ without even compiler >> vectorization >> (-ftree-vectorize) turned on, >> > > Are you sure? Fore example (and there are more of them), lots of these do > not seem marginal: > https://www.phoronix.com/scan.php?page=news_item&px=Clear-Linux-2019-Python-Perf > , https://www.phoronix.com/scan.php?page=article&item=linux-2016-2018&num=3 I see typically useless benchmarks without enough information, or profiles, that provide no real insight. These things rarely measure what they purport to; also error bars -- we've heard of them. Numpy is presumably dominated by level 3 BLAS (a library which is swappable on Ubuntu, as it should be in Fedora, with potentially two orders of magnitude performance difference in DGEMM), and whatever threading is used. I suspect similarly for the other things. First take Intel proprietary stuff out of the equation, and think about those numbers taken at face value. Note that using avx2 can be worse than sse2/4, and cache effects are often more important (as in optimized BLAS). _______________________________________________ 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
