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@likev
Created October 12, 2021 03:10
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when use global variables,the for loop run 100x slow in firefox dev console!
"use strict";
//when use global variables,the for loop run 100x slow!
const CHECK_LENGTH = 1E6,
CHECK_POINT = Math.ceil(Math.sqrt(CHECK_LENGTH));
var test1 = _ => {
let cn = new Array(CHECK_LENGTH);
for (let j = 2; j < 1E3; j++) {
for (let i = j * j; i < 1E6; i++) {
}
}
}
var test2 = _ => {
let cn = new Array(CHECK_LENGTH);
for (let j = 2; j < CHECK_POINT; j++) {
for (let i = j * j; i < CHECK_LENGTH; i++) {
}
}
}
var t1 = performance.now()
test1()
console.log(`without global variables: took ${performance.now() - t1} milliseconds.`)
var t2 = performance.now()
test2()
console.log(`with global variables: took ${performance.now() - t2} milliseconds.`)
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