Run results for: single for loop vs multiple for loops for iterating over arrays

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.36

Browser: Chrome 131

Operating system: Windows

Device Platform: Desktop

Date tested: one year ago

Test name	Executions per second
single loop (big N)	322.2 Ops/sec
separate loops (big N)	280.3 Ops/sec
single loop (small N)	345163.3 Ops/sec
separate loops (small N)	260841.3 Ops/sec

Script Preparation code:

const smallN = 2 ** 10
const bigN = 2 ** 20

const arr1 = []
const arr2 = []

for (let i = 0; i < bigN; ++i) {
	arr1.push(Math.random())
	arr2.push(Math.random())
}

Tests:

single loop (big N)
for (let i = 0; i < bigN; ++i) { arr1[i] *= 2 arr2[i] *= 2 }
separate loops (big N)
for (let i = 0; i < bigN; ++i) arr1[i] *= 2 for (let i = 0; i < bigN; ++i) arr2[i] *= 2
single loop (small N)
for (let i = 0; i < smallN; ++i) { arr1[i] *= 2 arr2[i] *= 2 }
separate loops (small N)
for (let i = 0; i < smallN; ++i) arr1[i] *= 2 for (let i = 0; i < smallN; ++i) arr2[i] *= 2

Run results for: single for loop vs multiple for loops for iterating over arrays

single loop (big N)

separate loops (big N)

single loop (small N)

separate loops (small N)