AlmaLinux, CentOS Stream, Clear Linux, Debian, Fedora & Ubuntu On AMD 4th Gen EPYC Genoa

Overall the tested Linux distributions were working well on the AMD EPYC 9654 2P server without any compatibility issues to note. When it comes to the out-of-the-box performance, the results can vary greatly. Clear Linux and CentOS Stream and AlmaLinux that all default to the performance CPU frequency scaling governor had an obvious advantage. Granted it's easy to enable the performance governor elsewhere if desired, but it's a shame that in 2023 more Linux distributions aren't defaulting to it when running on server CPUs. Some of the other performance differences such as around OpenJDK Java, PHP, and Python can be adjusted too with relative ease depending upon your version and performance requirements, while this article was just looking at the stock/out-of-the-box performance for each Linux OS tested.

Intel's Clear Linux with its AVX-512 optimizations and plethora of other package optimizations and other extensive tuning for optimal x86_64 performance certainly paid off for AMD 4th Gen EPYC "Genoa" performance... The flagship EPYC 9654 2P processors saw 27% faster performance than the next fastest Linux distribution, which was CentOS Stream 9. The slowest distribution tested on the AMD Titanite server was Ubuntu 22.10 at its defaults where there the out-of-the-box performance spread had a 41% advantage to Clear Linux based on the geo mean of all 110 different benchmarks. These numbers just reinforce the importance of software optimizations and tuning even for a high-end server with 192 cores / 384 threads. Especially now with AVX-512 on the AMD front, software tuning can be all the more pressing.

It would be great in 2023 to see more Linux distributions offer better out-of-the-box tuning for modern hardware (at least we're seeing some progress with x86-64 micro-architecture feature levels and the like) and also to see AMD become more engaged in software tuning/optimizations similar to Intel's extensive efforts over the years with Clear Linux and various software project upstreams.