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monitorEventLoopDelay - node__perf_hooks.d.ts - Node documentation
function monitorEventLoopDelay

Usage in Deno

```typescript import { monitorEventLoopDelay } from "node:node__perf_hooks.d.ts"; ```
monitorEventLoopDelay(options?: EventLoopMonitorOptions): IntervalHistogram
> [!WARNING] Deno compatibility > This symbol is not implemented. _This property is an extension by Node.js. It is not available in Web browsers._ Creates an `IntervalHistogram` object that samples and reports the event loop delay over time. The delays will be reported in nanoseconds. Using a timer to detect approximate event loop delay works because the execution of timers is tied specifically to the lifecycle of the libuv event loop. That is, a delay in the loop will cause a delay in the execution of the timer, and those delays are specifically what this API is intended to detect. ```js import { monitorEventLoopDelay } from 'node:perf_hooks'; const h = monitorEventLoopDelay({ resolution: 20 }); h.enable(); // Do something. h.disable(); console.log(h.min); console.log(h.max); console.log(h.mean); console.log(h.stddev); console.log(h.percentiles); console.log(h.percentile(50)); console.log(h.percentile(99)); ```

Parameters

optional
options: EventLoopMonitorOptions

Return Type