I was only talking about the instrumentation system on Android, not the one anywhere else. It forced ART to fall back to interpreted mode, so no JIT at all, which massively balloons the cost of certain things like single-line getters or JNI calls. It was actually useless as a performance tool of any kind, which is why the recommendation for years has been to ignore the numbers it produced. It's great at answering questions about what a given function ends up doing, but that's it.
If you want low-overhead timelines with duration numbers that actually have meaning that's the job of systrace ( https://developer.android.com/studio/command-line/systrace.h... ).