Hi Mark, On Apr 10 21:21, Mark Geisert wrote: > I've recently sent a patch to cygwin-patches that implements these > Linux-specific functions. I used the following test program to debug and > test the implementation. When the program is run, you can watch it migrate > from CPU to CPU with Windows Task Manager. > > I've only tested on 64-bit Windows 7 so far. If the code (in the patch) is > adequate I will supply another patch for doc updates, etc. Your patch is nicely done, but what about machines with more than 64 CPUs? Your patch only uses the standard API for up to 64 CPUs, so a process can never use more than 64 CPUs or use CPUs from different CPU groups. There was also the case of this weird machine Achim Gratz once worked on, which had less than 64 CPUs but *still* used multiple CPU groups under Windows, for some reason. Any chance you could update your patch to support this functionality? For some info, see MSDN: https://docs.microsoft.com/en-us/windows/desktop/ProcThread/processor-groups Also, there's already some code in fhandler_proc.cc, function format_proc_cpuinfo to handle CPU groups. You can use the wincap.has_processor_groups() method to check if the system supports CPU groups. Thanks, Corinna -- Corinna Vinschen Cygwin Maintainer