Benchmark: For loop initialization.

Script Preparation code:

const count = 22000;

Tests:

Index - Initial Size Set
const count = 25000; let a = new Array(count); for(let i=0;i<count;i++) { a[i]=i; }
Index - Initial Size Not Set
const count = 25000; let a = []; for(let i=0;i<count;i++) { a[i]=i; }
Array.push
const count = 25000; let a = []; for(let i=0;i<count;i++) { a.push(i); }

Rendered benchmark preparation results:

Previous results

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Latest run results:

Run details: (Test run date: 5 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_12_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/60.0.3112.113 Safari/537.36

Browser/OS: Chrome 60 on Mac OS X 10.12.6

For loop initialization. (version: 10)