This is getting perilously close to "attempting to extract performance information from a program running under a simulator/CPU model", which is really tricky t

This is getting perilously close to "attempting to extract performance information from a program running under a simulator/CPU model", which is really tricky to do in a way that gives you results that apply to actual hardware. In particular, the performance characteristics of QEMU are wildly different from real hardware in several significant ways: (1) the emulated FPU is incredibly slow, so the results will overweight anything that's FP-intensive (2) there is no modelling of CPU caches, TLBs or branch predictors, so these major influences on real-hardware performance won't be visible (3) because the emulated CPU is very slow, interrupt handler and similar code which runs triggered by timers or other external events will take up more time in the trace than it would on hardware. You'd probably find something interesting in the general sense from looking at what's going on in a QEMU emulation for a fixed time period, but you'd need to be rather wary about how applicable what you saw might be to a real hardware run. At minimum you'd want to cross-check against what perf on real hardware revealed.