'roughly' is really poorly defined. CPUs leverage things like branch prediction and context switching, and also CPUs and GPUs both need to be designed for appro

'roughly' is really poorly defined. CPUs leverage things like branch prediction and context switching, and also CPUs and GPUs both need to be designed for approximately arbitrary use cases, which is a much harder thing to do than designing for random input. If you know for certain that the operations you get will follow some distribution, you can customize towards that distribution in ways a cpu or gpu can't.