Request Timeouts increase eventloop lag

[gchicoye]

Describe the bug

• Node.js version: v18.17.1
• OS & version: node:lts-alpine
• Got v12.6.1

Actual behavior

When the quality of network decreases and timeout increases, event_loop_lag increases.
See below timeout percentage and eventloop.

My timeout is from 450 ms to 500 ms for outgoing queries.
Any idea?

Expected behavior

I expect event_lag to remain stable although network quality decreases...

...

Code to reproduce

To be further discussed

;

Checklist

• I have read the documentation.
• I have tried my code with the latest version of Node.js and Got.

[roy-algaly]

it could be the other way around, due to issues with event loop you started to get increase timeouts

[sindresorhus]

The causation is likely reversed here: event loop lag causes timeouts, not the other way around.

I tested Got with 1000 concurrent timeouts and found event loop lag increase was negligible (~0.01ms average). Got's timeout implementation uses unref()'d timers and defers timeout errors with setTimeout(..., 0), which is actually optimized to avoid blocking the event loop.

You're using v12.6.1, which predates PR #2399 that specifically improved timeout behavior during event loop congestion. Upgrading to v14.x would help reduce spurious timeouts when your event loop is busy.

The real issue is something else in your application causing event loop lag (blocking operations, heavy sync code, slow database queries, etc.), which manifests as both increased timeouts and observable lag. I'd recommend using tools like perf, 0x, or Node.js's built-in profiler to identify what's actually blocking your event loop.

Closing this as not a bug in Got.