Was I really just able to allocate 56GB of memory in Google chrome?

56GB.js

var x = [];
for (var i = 0; i < 56; i++) {
  x.push(new Uint8Array(1024 * 1024 * 1024));
}
console.log(x.length);

Can confirm it works.

It's not until you start accessing that memory that it really gets mapped in by the system, so on a 64bit OS you can "allocate" huge amounts but you can't use it all, since your machine will reach some limit before it gets all used up and mapped in. But there is some room for jokes on browser memory consumption here. =)

@icepic are you saying this is happening by the browser? Or at the OS level? https://twitter.com/vicapow/status/655248145316642816?s=17

Here, I allocate 50GB, assign each byte a random value [0, 256) and accumulate the result. One downside, as far as I can tell, you can't allocate a single TypedArray larger than 1GB.

This took ~23min to run but didn't crash!

var t0 = Date.now();
var x = [];
var GB1 = 1024 * 1024 * 1024;
var i;
var j;
var gigs = 50;
for (i = 0; i < gigs; i++) {
  x.push(new Uint8Array(GB1));
  for (j = 0; j < GB1; j++) {
    x[i][j] = Math.random() * 256 | 0;
  }
  console.log('gig', i);
  console.log('t', Date.now() - t0);
}

i = 0;
var accum = 0;
for (i = 0; i < gigs; i++) {
  for(j = 0; j < GB1; j++) {
    accum = accum + x[i][j] - 128;
  }
  console.log('gig', i);
  console.log('t', Date.now() - t0);
}

console.log('accum', accum);