pop vs shift on a array (v36)

Revision 36 of this benchmark created on

Description

If you can choose between a .pop() or .shift() on a Array, what would be a wise decision?

As my http://jsperf.com/adding-items-array/6 test shows the unshift is awful for performance. The same counts for .shift(), awful performance.

Test runner

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Testing in
TestOps/sec
.pop()
var array1 = new Array(200000);
var i = array1.length;

 array1.pop();
 
ready
.shift()
var array1 = new Array(200000);
var i = array1.length;

 array1.shift();
 
ready
.splice beginning
var array1 = new Array(200000);
var i = array1.length;

 array1.splice(0, 1);
 
ready
.splice end
var array1 = new Array(200000);
var i = array1.length;

 array1.splice(i, 1);
 
ready
Decrement .length
var array1 = new Array(200000);
var i = array1.length;

 array1[i];
 // Beware, setting the length to < 0 will throw an exception
 --array1.length;
 
ready
Reverse
var array1 = new Array(200000);
array1.reverse();
 
ready
unshift
var array1 = new Array(200000);
var i = array1.length;

 array1.unshift(1);
 
ready
pop second
var array1 = new Array(200000);

 array1.pop();
 
ready

Revisions

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