I'm not sure whyu it's using only one core for JIT, but JITIL should be marginally faster than JIT on a 32bit OS anyway (as far as I can remember).
OS: Windows 10 64 bit Professional
CPU: AMD Ryzen 5900X
RAM: 16GB
GPU: Radeon Vega 56
CPU: AMD Ryzen 5900X
RAM: 16GB
GPU: Radeon Vega 56
