| If there was an actual energy efficiency advantage -- i.e. less power consumed for the same amount of work -- Google would already be 100% on ARM. Why do you think they would leave that on the table? I realize the situation changes every time a new CPU comes out, but I have never personally seen a real workload where ARM won on energy efficiency and had reasonable performance. Tests like [1] and [2] showing x86 having an orders-of-magnitude lead on database performance vs. AWS Gravitron2 should give you serious pause. 1: https://openbenchmarking.org/embed.php?i=2005220-NI-GRAVITON... 2: https://openbenchmarking.org/embed.php?i=2005220-NI-GRAVITON... If you're wondering why ARM needs to have both competitive performance and energy efficiency, see Urs Holzle's comments on wimpy vs. brawny[3]. 3: https://static.googleusercontent.com/media/research.google.c... |
Hello,
There definitely is that power use advantage.
Those tests are pathological cases because of bugs, and aren't representative of the performance of the hardware. (for that one I suspect that ARMv8.1-A atomics weren't used in compiler options...)