When I worked at Facebook, I worked on a web memory tracking tool I was particularly proud. It went through links, grabbed heap snapshots, diff'ed them, found objects that weren't cleaned up and gave detailed information about its retain chain. You can see a lighting talk I did on it at BlinkOn: https://www.youtube.com/watch?v=JuyaGFApifA&t=1427s&ab_chann...
Colleague of bgirard at Facebook here, we are planning to open source the tool in 2022. Great to find someone also working on memory tooling here :) Fuite seems really interesting, will try it out!
Author here. I wasn't aware of your talk, but it's super interesting! Showing info about the retain chain is a great idea, but I didn't get around to doing it in fuite. IME just counting the number of objects is actually pretty effective to find the smoking gun. (You leaked 1 event listener, which leaked a bazillion strings, arrays, objects, etc., but all you really care about is the 1 event listener.)
I would love to see how your tool approaches this! Hope it gets open-sourced. :)
Hi bgirard! I support the FB team that works on this - it's on the roadmap to open source hopefully H1 next year :) It's continued to find significant leaks in other parts of our infra too, so hopefully it will be equally helpful to others. Great to see others looking at memory tools now too - I'll definitely be checking Fuite out
We used it to find a problem fixed in React 18 that caused large leaks on Facebook.com: https://github.com/facebook/react/pull/21039#issuecomment-80...
We also found one issue that caused a leak that's impossible to spot unless you know how V8 closures are implemented and retain one another.
I'm really hoping to see Facebook open source the tool some day!
Fuite seems really interesting. I like the idea of an automatic crawler!