Global Variables vs Local Variables

JavaScript performance comparison

Revision 2 of this test case created by Todd

Preparation code

<script>
  var a,b=0;
  function x() {
    for(a=0;a<20;a++)
      b+=a;
  }
  function y() {
    var c,d=0;
    for(c=0;c<20;c++)
      d+=c;
  }
  function z(){
    var c = a,
        d = b;

    for(c=0;c<20;c++)
       d+=c;
  }
</script>
    

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Testing in CCBot 2.0.0 / Other 0.0.0
Test Ops/sec
Global variables
x();
pending…
Local variables
y();
pending…
Cached global variables
z();
pending…

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Revisions

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