A Look At The Windows vs. Linux Scaling Performance Up To 64 Threads With The AMD 2990WX

First up was John The Ripper with the Blowfish algorithm. JTR utilizes OpenMP for multi-threading and is able to successfully scale up to 64 threads. From this first test it's interesting to note that in the SMT-enabled configuration the Windows performance actually was degraded but Linux continued to successfully scale up to the 64 threads. In the end for the Blowfish test going from 4 to 64 threads yielded a 7.5x increase in Linux performance or 6.39x for Windows (or 7.77x for Windows at 32 threads).

Continuing with John The Ripper, the traditional DES test saw the Windows performance to also drop when SMT was enabled while Linux had a small benefit from all 64 threads. The relative performance of Windows vs. Linux was scaling in step between operating systems up until the 24 thread configuration when Ubuntu Linux was pulling ahead with better scaling.

The x264 video encoding performance was quite close between Windows and Linux at 32 threads while at lower thread counts is where Linux was running noticeably better in this video encoding test. With SMT enabled was another case where Windows Server 2019 regressed hard -- to the point of being slower than the 24 thread configuration -- while the Linux 64-thread performance was in line with the 32-thread performance.