JavaScript typed arrays for all variables?

Question

I am writing some code for a research project. I am writing it in javascript because I want to be able to run it anywhere and to be able to publish it on the web when I finish the project. But I also need to rerun this code hundreds of thousands of times and look at the results as part of the research project so I want it to be efficient. For the webgl part of the project I am using an array buffer and typed arrays.

Would using an array buffer or typed array for all the javascript variables give normal javascript any performance improvements?

---

From what I have read it sounds like this is what web assembly and some transpilers are doing.

Answer 1

It is definitely possible to take advantage of some of the same typed array techniques that give web-assembly their boost. However as can be seen in the code snippet, naively replacing JS standard array with a typed array does not affect performance in any major way on e.g Chrome. (In fact, in the example the observed effect was negative)

let a = [];
let A = new Float64Array(1000000)
let b = [0, 0, 0, 0, 0, 0, 0, 0];
let B = new Float64Array(8);
for (let i = 0; i < 1000000; i++) {
  let v = Math.sqrt(1+i)
  a[i] = v;
  A[i] = v;
}


tn = performance.now()
for (let n = 0; n < 500; n++) {
  for (let i = 0; i < 999999; i++) {
    B[i % 8] = B[i % 8] + (A[i] * A[i])
  }
}
let SUM = 0;
for (let i = 0; i < 8; i++) {
  SUM = SUM + B[i];
}
console.log("   TYPED ARRAY", performance.now() - tn, SUM)


tn = performance.now()
for (let n = 0; n < 500; n++) {
  for (let i = 0; i < 999999; i++) {
    b[i % 8] = b[i % 8] + (a[i] * a[i])
  }
}
let sum = 0;
for (let i = 0; i < 8; i++) {
  sum = sum + b[i];
}
console.log("standard array", performance.now() - tn, sum)