│ before │ after │ │ sec/op │ sec/op vs base │ X 100.0n ± ∞ ¹ 101.0n ± ∞ ¹ ~ (p=1.000 n=1) ² ¹ need >= 6 samples for confidence interval at level 0.95 ² need >= 4 samples to detect a difference at alpha level 0.05