intermediateJVM Internals & Memory

Why is naive Java benchmarking (System.nanoTime() around a loop) misleading?

It measures code before JIT warm-up completes (so you're timing the slow interpreted version), can be skewed by a GC pause landing inside the measurement window, and the JIT can eliminate 'dead' code that computes a result nobody uses — all of which produce numbers that don't reflect real steady-state performance.

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