3 ms·
In the "power" section, it seems the analysis doesn't divide by the number of instructions executed per second. Energy used per instruction is almost certainly
by londons_explore 2y ago
In the "power" section, it seems the analysis doesn't divide by the number of instructions executed per second.
Energy used per instruction is almost certainly the metric that should be considered to see the benefits of this loop buffer, not energy used per second (power, watts).
- eek2121 2y agoEvery instruction takes a different amount of clock cycles (and this varies between architectures or iterations of an architecture such as Zen 4-Zen 5), so that is not feasible unless running the workload produced the exact same instructions per cycle, which is impossible due to multi threading/tasking. Even order and the contents of RAM matters since both can change everything. While you can somewhat isolate for this by doing hundreds of runs for both on and off, that takes tons of time and still won’t be 100% accurate. Even disabling the feature can cause the code to use a different branch which may shift everything around. I am not specifically familiar with this issue, but I have seen cases where disabling a feature shifted the load from integer units to the FPU or the GPU as an example, or added 2 additional instructions while taking away 5.