Bad Gateway 502/504

[remy]

You might have seen one of these errors in the past.

What you're seeing is when nginx (our proxy) isn't able to hit jsbin's node process.

This could be that the node process is down (which is very rare, but can happen during emergency maintenance—though of course I'd rather avoid where possible).

What I'm seeing more often lately is the node process is spinning out of control at 99% CPU. I've run an strace on the node process, but absolutely nothing is happening.

This was the trace: https://gist.github.com/remy/9cf7a03caac6acc00a83

This is an example of trace during normal CPU utilisation: https://gist.github.com/remy/9fa21ec5a17408882440

The big difference is you can see something is going on in the normal use.

Today I upgrade from node v0.8.x to v0.10.13. Though not confident this will make any difference. Some IRC folk have suggest it could be GC going out of control, but I'm not too sure what I can do about it.

Totally open to ideas, and will keep posting on this thread there's updates.

[allouis]

https://hacks.mozilla.org/2012/11/tracking-down-memory-leaks-in-node-js-a-node-js-holiday-season/ this could be useful for this. I'm sure there is a duplicate of this issue somewhere but i cannot find it.

[remy]

Turned out to be stylus. Long since fixed via jsbin/pennyworth.