Behavior of monitorEventLoopDelay when called from a Worker

[jeluard]

When called from a Worker, what is the expected behavior from monitorEventLoopDelay?
Shall it report main JS thread event loop delay, or this worker thread's one?

eventLoopUtilization also exists on Worker, suggesting monitorEventLoopDelay always monitors main JS thread?

[DarkGL]

It should report worker thread event loop delay

For example

const { Worker, isMainThread, parentPort } = require('worker_threads');
const { monitorEventLoopDelay } = require('perf_hooks');

if (isMainThread) {
  const worker = new Worker(__filename);
  worker.on('message', (message) => {
    console.log(`Received message from worker: ${message}`);
  });
} else {
  const histogram = monitorEventLoopDelay();
  histogram.enable();
  
  setTimeout(() => {
    histogram.disable();
    parentPort.postMessage(`Worker event loop delay: ${histogram.percentile(50)} ms`);
  }, 1000);
}