How to get a thread dump of a running Node.js process?

Question

In the Java JVM, kill -3 forces the process to print the current stack traces of all running threads. I found it very effective to quickly locate bottlenecks.

Is there an equivalent in V8? Can I make V8 print the current stack trace?

Clarification:
I assume, due to the asynchronous nature of node, it will be less useful than for a typical non-asynchronous program. Still, if there is an easy way to get access to a few stack traces, it does not take much time to look at it.

From my experience, some obvious bottlenecks can be quickly located that way before you need to switch to more advanced tools.

Viral Patel · Answer

You can accomplish the same using heapdump tool. I found the below article of the same which is below (It also works for me):
https://medium.com/better-programming/make-a-dump-of-the-v8-heap-and-inspect-for-your-node-app-b69f7b68c162

zvi · Answer

On this thread you have an idea using:
# node --debug-brk buggy.js Debugger listening on port 5858
In another terminal:
connecting to 127.0.0.1:5858 ... ok
break in buggy.js:16
 14 }
 15 
>16 z();
 17 
 18 });
debug> cont```

(wait for the node process to start using 100% CPU)

```debug> step
break in buggy.js:3
  1 function x() {
  2     var i = 0;
> 3     while(1) {
  4             i++;
  5     }
debug> bt
#0 buggy.js:3:8
#1 buggy.js:9:2
#2 buggy.js:13:2
#3 buggy.js:16:1```

Source:
https://github.com/nodejs/node-v0.x-archive/issues/25263

Aditya Guru · Answer

Node has fully loaded diagnostics that tricks like above (if I understood correctly) would be redundant but feel free to correct me.
Must Read: Awesome blogs by NodeSource 1 2 3
I'll try to list down all the tools that I found useful:

Diagnostic Reports

v8 profiler

Flame Graphs

why-is-node-running

trace

clarify

Others (Just googled them.)

N|Solid by NodeSource
Autopsy
StackImpact

How to get a thread dump of a running Node.js process?

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