A7 does not need "performance" at all here. An empty script can not have any performance.

When you want to measure the performance of an engine, you must use some sort of test application. When the engine does not do anything, you obviously can not measure anything. The 5% you've got are probably a random value caused by the smoother frame rate adjustment of A7 due to 'burning' of CPU cycles. This is the only thing that happens at all in your test. If you're interested, you can find details about that burning under "fps_max" in your manual.