AMD Zen 4 AVX-512 Performance Analysis On The Ryzen 9 7950X

For the Leela Chess Zero (LC0) chess program that makes use of neural networks, the AVX-512 path on the Ryzen 9 7950X led to a 10% speed-up compared to without AVX-512 (leaving just AVX / AVX2). Okay, so a 10% boost is nice, but what about the impact on power consumption?

There was no significant change to the CPU power consumption during the AVX-512 execution. In fact, the RAPL-reported values were 3 Watts lower on average than when AVX-512 wasn't used...

The CPU peak frequency and CPU temperature also showed no significant change when AVX-512 support was used. That's looking much better compared to the impact when AVX-512 first premiered with Skylake-X and seeing often significant downclocking during AVX-512 usage with heavy power/thermal penalties.

One of the recent notable adopters of AVX-512 was the simdjson project showing AVX-512 can provide better performance for JSON parsing... Like on the Intel side, the latest simdjson release shows AVX-512 can be of benefit here too.

AVX-512 usage on the Ryzen 9 7950X meant 26% better performance in some of the JSON parsing benchmarks.

All the while there was similar CPU power consumption and temperature when AVX-512 was being utilized.

So far the AVX-512 performance with the AMD Ryzen 9 7950X is looking quite good even with not employing a 512-bit data path.