The most upvoted question/answer on stackoverflow is this one: https://stackoverflow.com/questions/11227809/why-is-processing-a-sorted-arra... I wanted to see if the results could be reproduced in Pharo, and indeed they can (though I only get a factor 2-3 difference). The following method does the trick: branchPrediction | size data rnd sum start | size := 32768. data := ByteArray new: size. rnd := Random new: 0. 1 to: size do: [ :i | data at: i put: (rnd nextInt: 256) - 1 ]. âsorting the array makes the loop faster" data sort. sum := 0. start := DateAndTime current. 10000 timesRepeat: [ 1 to: size do: [ :i | (data at: i) > 128 ifTrue: [ sum := sum + (data at: i) ] ] ]. ^ {(DateAndTime current - start) asMilliSeconds. sum} Though it is old news, it is still kind of cool. Best, Kasper