Did my Javascript run out of asyncIds ? (RangeError in inspector_async_hook.js)

Question

First i use async and await very often and i get this error:

RangeError: Value undefined out of range for undefined options property undefined
    at Set.add (<anonymous>)
    at AsyncHook.init (internal/inspector_async_hook.js:19:25)
    at PromiseWrap.emitInitNative (internal/async_hooks.js:134:43)

And i dont know how i can fix this, i write my code completly in Typescript and i dont created any file that is named 'async_hooks'.

And i dont run more then 10 function async at once i use await very often so it shouldnt stack up but javascript seems not to reduce the asyncId and reach the number limit very fast.

I tried to use less async await but this didnt fix the problem, but the error msg comes later. If i use very less async await i can prevent that this error comes until the function successfully finish the job. (I use Electron 7)

Electron seems to have a very low async pool but it can be reproduced by a default typescript code:

class Test {
    private async testCompare(a,b):Promise<boolean> {
        return a == b;
    }

    public async testRun():Promise<void> {
        for (let index = 0; index < 999999999; index++) {
            for (let index2 = 0; index2 < 999999999; index2++) {
                await this.testCompare(index,index2)
            }
        }
    }

}
new Test().testRun();

This Code produce very much ram usage, and i think i have the same problem in my program. I think that the async pool get filled up until it reached its limit.

Answer 1

I got the same error for Set.add as you did once my set size reached 16777216 (2^24). I'm unable to find the info on this limit in the documentation, but I'll assume sets are limited to 16777216 unique values?

Easily tested with a simple for loop.

This will throw the exact same error:

let s = new Set();
for (let i = 0; i <= 16777216; i++) s.add(i);

This will run successfully:

let s = new Set();
for (let i = 0; i < 16777216; i++) s.add(i);

Do note that this will eat up some ~5GB of memory, so increase your heap limit accordingly if it's crashing due to memory restrictions.

Answer 2

Just encountered this using a Set, i used the following as a quick workaround

class Set {
  hash = {}

  add (v) {
    this.hash[JSON.stringify(v)] = true
  }

  has (v) {
    return this.hash[JSON.stringify(v)] == true
  }
}

this has no limit, only limited by your systems memory