Array push() vs unshift() (v36)

Revision 36 of this benchmark created by Pete L on

Description

Tests the performance difference of using two different ways of filling arrays at the start. The two TCs produce the same result.

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Testing in
TestOps/sec
push()
var a = [];
a.push(22);
a.push(21);
a.push(20);
a.push(19);
a.push(18);
a.push(17);
a.push(16);
a.push(15);
a.push(14);
a.push(13);
a.push(12);
a.push(11);
a.push(10);
a.push(9);
a.push(8);
a.push(7);
a.push(6);
a.push(5);
a.push(4);
a.push(3);
a.push(2);
a.push(1);
a.reverse();
var v = 0;
for (var i = 0; i < a.length; i++) {
  v += a[i];
}
ready
unshift()
var a = [];
a.unshift(22);
a.unshift(21);
a.unshift(20);
a.unshift(19);
a.unshift(18);
a.unshift(17);
a.unshift(16);
a.unshift(15);
a.unshift(14);
a.unshift(13);
a.unshift(12);
a.unshift(11);
a.unshift(10);
a.unshift(9);
a.unshift(8);
a.unshift(7);
a.unshift(6);
a.unshift(5);
a.unshift(4);
a.unshift(3);
a.unshift(2);
a.unshift(1);
var v = 0;
for (var i = 0; i < a.length; i++) {
  v += a[i];
}
ready
push, iterate in reverse order
var a = [];
a.push(22);
a.push(21);
a.push(20);
a.push(19);
a.push(18);
a.push(17);
a.push(16);
a.push(15);
a.push(14);
a.push(13);
a.push(12);
a.push(11);
a.push(10);
a.push(9);
a.push(8);
a.push(7);
a.push(6);
a.push(5);
a.push(4);
a.push(3);
a.push(2);
a.push(1);
var v = 0;
for (var i = a.length - 1; i >= 0; i--) {
  v += a[i];
}
ready

Revisions

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