In Linux you can use numactl command to pin a process.

Windows has a NUMA API[1] to help with these things. For pinning a thread you can for example use the SetThreadSelectedCpuSetMasks call[2] from what I can gather.

[1]: https://docs.microsoft.com/en-us/windows/win32/procthread/nu...

[2]: https://docs.microsoft.com/en-us/windows/win32/api/processth...

libnuma probably does the job.

https://github.com/numactl/numactl

If you want to do set thread-core affinity in a cross-platform way, hwloc is a good approach: https://www.open-mpi.org/projects/hwloc/doc/v2.7.0/a00166.ph...