discussion/question - api implementation makes sense just not quite expected

[ORESoftware]

I enjoyed the old domain API, something like this:

const Domain = require('domain');
const d = Domain.create();

d.run(() => {
    console.log('running');
});

d.once('error', e => {
    console.error('domain caught:',e);
});

throw 'boop'

boop would not get captured by the domain, instead it bubbles up to global space

however, when using AHD - we have:

const ahd = require('async-hook-domain');

const d = new ahd.Domain(err => {
    console.error('AHD caught:',err);
});

throw 'boop'

and boop will get captured by AHD.

So this begs the question, does the original domain module process.nextTick() when it executes the run method? I looked through the source back in the day and didn't notice that - but I suspect if so, that could be one of the biggest sources of slower performance?! And again if so, it would be very hard to change the old core domain API to not process.nextTick...so maybe that's why original domain is stuck deprecated. just a theory.

[ORESoftware]

nevermind, it doesn't process.nextTick, it does this:

Domain.prototype.run = function(fn) {
  this.enter();
  const ret = ReflectApply(fn, this, ArrayPrototypeSlice(arguments, 1));
  this.exit();  // here
  return ret;
};

so then I can't explain to myself why the original implementation should be slow. So I am wondering what the culprit is/was. Current implementation is partly based off async-hooks - https://github.com/nodejs/node/blob/main/lib/domain.js#L74C31-L74C31