3 ms·

thanks for the detailed info. phoronix.com just published some Power9 vs. Xeon vs Epyc benchmarks[1]. It is actually not on par with Xeon/Epyc. also note that

• dragontamer 8y ago
  A lot of the "weakness" there is due to the weak 4x64-bit vector units equipped on the Power9. Again: 4x64-bit vector units (Power9) simply has less throughput than 4x128-bit (EPYC) units, which has less throughput than 3x512-bit (Xeon Gold) vector units. On the few tests which don't have anything to do with vector units, Power9 does incredibly well. See 7-Zip Compression, Stockfish, Fhourstones, LLVM compiles. Power9 is very, very far ahead of the game here. When vector units (ie: OpenMP or intrinsics) are involved: such as Parboil, Gimp, x264, Rodinia, etc. etc. the Power9 does very poorly. ------------- Something else I've noticed: Power9 has a lot of latency behind its units: it is always 2-cycles or 3-cycles of latency (while EPYC or Skylake have many operations with 1-cycle of latency, like add or subtract). Power9 relies upon instruction-level parallelism to get things done. So there are a few cases like the Rust Mandelbrot benchmark, which surely hits that latency problem, while the Rustlang Prime benchmark shows off the ILP goodness the system offers.