1 to: 100 do: [:i|]. ** Pure interpretation: Hits: 407 Misses: 214 Hits: 411 Misses: 210 Hits: 409 Misses: 212 ** After compilation to vector-instructions: Hits: 610 Misses: 11 Hits: 618 Misses: 3 Hits: 618 Misses: 3 n@(Number traits) fib [ (n < 2) ifTrue: [ n ] ifFalse: [ (n - 1) fib + (n - 2) fib ] ]. csi> (time (do ((i 0 (+ i 1))) ((= i 10)) (fib 20))) 0.59 seconds elapsed 0.09 seconds in (major) GC 1 mutations 111 minor GCs 21 major GCs .... ThiNG took 112 seconds for a (20 fib).