Making Programs Faster

The Uncertainty Principle

There's another way to try to eliminate bias
- You can try to correct for it
- By adding a lot of complicated machinery to measure bias and subtract it from the results
This is the Benchmark.pm approach
But if it goes wrong, you have no idea what really happened

      null: -1 wallclock secs
        (-0.07 usr +  0.01 sys = -0.06 CPU) 
        @ -16666666.67/s (n=1000000)

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