AMD EPYC 7003 "Milan" Linux Benchmarks - Superb Performance
In highly threaded workloads that are well optimized for ARMv8, Ampere Altra can compete or in some cases even outperform Milan but it really depends how well optimized your particular code-base / workloads are tuned for non-x86_64.
In many cases, Ampere Altra poses more competition to Milan than Intel's current Xeon processors.
In single threaded tests like Python / Numpy and PHP, the x86_64 AMD/Intel processors hade a sizable lead in those single-threaded test cases.
With that subset of 62 tests of benchmarks that are supported on ARMv8 and have at least a similar level of tuning/compatibility across the benchmarks, the Ampere Altra Q80-33 2P surpassed the Xeon Platinum 8280 2P processors but overall based on the geometric mean of all the data points came up short of Milan. At this stage it really still depends upon the code-bases / workloads of importance to you for how viable ARMv8 servers are if the code is already well supported on ARMv8 and having at least a similar level of optimizations to x86_64 for performance sensitive areas. See this OpenBenchmarking.org result file for more of these EPYC/Xeon/Altra benchmarks. Further benchmarks will come in follow-up articles.
Ampere is also preparing Altra Max that can offer up to 128 cores per socket but its clock speeds are unknown. Meanwhile with AMD EPYC "Genoa" Zen 4 next year at 5nm is rumored to offer up to 96 cores per socket... Interesting times and healthy competition ahead!