How to trigger profiling in NodeJS at runtime?

Question

We have a very stateful NodeJS based web server (Meteor) that occasionally, randomly becomes slow in production. The problem is not reproducible in any of our tests, and we don't know what's triggering it.

To diagnose this, we are using the v8-profiler package. This lets us trigger a 10-second CPU profile and download it for offline analysis.

Despite not having received any commits in 3 years, the package used to work fairly well. It has given us compilation trouble in the past, and now it looks like it stopped compiling entirely, breaking our build. The build happens inside a Docker container with all versions pinned, including NodeJS and v8-profiler itself, so it's unlikely that we can fix this on our end.

I'm thinking there must be some alternative, better maintained approach. But where is it?

(Note that restarting the server with additional flags (like --profile) is not an option, because it destroys all the evidence of the problem.)

Answer 1

I found there has been v8-profiler-next which is a successor of v8-profiler.

I hope this works for you.