Team avoids publishing false 2-4x slowdown after discovering benchmark timing flaws

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Engineers at Samyama Graph nearly released a performance report falsely claiming three database queries had regressed by 2–4x in speed. The errors stemmed from comparing benchmarks run hours apart on the same machine, which had drifted due to thermal throttling, frequency scaling, or background load. When all queries were re-run back-to-back in a single session, the supposed regressions vanished and one query actually proved nearly 2x faster. The team also found run-to-run variance of up to 24% on the same binary, meaning genuine regressions below that threshold could go undetected. In response, they introduced calibration checks at the start and end of each benchmark run and now require all before-and-after comparisons to come from a single uninterrupted session on one machine.

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