So instead of sampling, or hw perf counters, IPT does tracing? perf counters are able to attribute cycles or cache misses to instructions. but only in aggregate. If your program isn't a 100% computation, cycles consumed won't necessarily point to the bottleneck. So IIUC IPT can tell you more than just the statistics but instead can tell the real story - the sequence of instructions executed? If so, I can see this painting a much clearer picture. But what are the limitations? some small buffers that overflow after a few million instructions or pipeline flushes? If the IPT buffer(s) overflow does magic-trace indicate gaps?
Is it possible to combine PMU or sampling with IPT to get multiple profiling dimensions in the same run? Not just what sequence of instructions were executed but where in time-and-code the branch mispredictions, cache misses, etc. occurred?
Is it possible to combine PMU or sampling with IPT to get multiple profiling dimensions in the same run? Not just what sequence of instructions were executed but where in time-and-code the branch mispredictions, cache misses, etc. occurred?