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It says something like "without interference, some execution path has proven to be as fast as x". This probably isn't exactly what you wanted to know (e.g. expected time), but is likely to be much faster to compute for some thing that's probably usually strongly correlated.

The problem with the existence of 100 independent states is that you need a very large number of trials to get a performance measurement of each—and you're still left with the problem of statistic to reduce each to (min? mean? and how??). Attempting to take the mean with the CST should eventually work, but it might need a very long time. Instead, the minimum lets to pick whichever mode was fastest and compare the time of that mode. Sure, that might not be great for all cases, but if that's the worst problem with the benchmark suite, I'd say you're in pretty good shape. I've run into issues where the CPU appears to have memorized the random number sequence in the test data—how are you supposed to pick the better algorithm when the CPU won't let you run the 99% case under a benchmarking harness...

Yeah, minimum isn't perfect, but it's at least pretty clear what it says, as long as there isn't incentive to abuse it (I might say the same about p-value vs bayesian).

disclosure: worked with the author of the Julia paper cited above.



> Yeah, minimum isn't perfect, but it's at least pretty clear what it says

You’ve lost me. What is the single, obvious meaning of the minimum measurement, and what are you benchmarking against, and what do you intend to get out of the benchmark? Typically the minimum just means “program ran x input as fast as y”, which doesn’t actually help with most questions about performance.

If X is constant, and time is the only thing you care about, then maybe that works.


> which doesn’t actually help with most questions about performance.

well, from a marketing standpoint it means that you are able to write

OBSERVED MAXIMUM SPEED : 789634 gigabrouzoufs per second on a core i5-xxxx

on your brochure, and you wouldn't be lying, and it would be better that a majority of products which don't even give an observed speed but just a theoretical one.




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