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Comment by function_seven | Hacker News Reader

I just repeated your test, but got opposite results:

    $ time /usr/bin/true

    real 0m0.003s
    user 0m0.001s
    sys	 0m0.002s

    $ time /usr/bin/truth

    real 0m0.001s
    user 0m0.000s
    sys	 0m0.001s

I can't imagine for the life of me how an empty file could perform worse than an actual binary, but there's gotta be a reason.

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If you're relying on an empty binary, or exit 0; instead of an actual binary you have to execute a shell process to evaluate it. The binary doesn't need to load a shell, it can just do a bit of setup, then make a single exit 0 system call.

Thank you. That makes sense. So basically the empty file is seen by the shell as a "script" that has to be evaluated, so a separate shell process is spun up to handle it? And the difference between my output and the parent's has to do with some difference in our environments?

this is what happens when we aren't allowed to use p values anymore :)

https://www.sciencebasedmedicine.org/psychology-journal-bans...

The default p is p = 0.5, so I have no trouble accepting both your conclusion and your parent's :)

seriously though, this is why we use significance testing in real fields, like computer science...

Exactly. I did the most naive thing possible and only once for each version of true/truth. I was just bored/curious.

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