This talk goes into it a bit more: https://developer.apple.com/videos/play/tech-talks/110147 https://developer.apple.com/videos/play/tech-talks/110147 So it is

This talk goes into it a bit more: https://developer.apple.com/videos/play/tech-talks/110147 https://developer.apple.com/videos/play/tech-talks/110147 So it is possible to get a bit more control, at least on Apple ARM chips, but it’s intended for games. They even mention professional apps needing high performance are able to get the performance they need with the normal Dispatch APIs. There is no locking threads to cores, but you can set thread affinities as hints if you think certain threads should or should not share L2 cache (at least for intel based Macs). https://developer.apple.com/forums/thread/44002 https://developer.apple.com/forums/thread/44002