Does nixos-rebuild --cores N include CPU threads?

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1

For instance, my CPU has 8 cores and 16 threads. If I do nixos-rebuild --cores 6, will it use 6/8 cores or 6 threads? I looked at the man page nixos-rebuild --help but it didn’t say what --cores does.

2

I think this translates to Tuning Cores and Jobs - Nix 2.32.2 Reference Manual

3

Build processes on Linux see 16 “cores”. That has nothing to do with nix. How your cpu schedules said threads is up to your kernel’s scheduler and your cpu’s design.

Also see I/O & CPU scheduling, jobs & cores... and performance, baby - #4 by justinas for some context.

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