[erichocean]

What it means is that unless you are comfortable modifying Erlang itself (BEAM, internal data structures, hash table allocations, etc.), then your install of Erlang won't scale like WhatsApp. You'll also need a ton of monitoring because Erlang definitely isn't of the "just turn it on, it'll be fine" variety. Nothing at that scale is.

That's fine, but people do tend to oversell Erlang IMO. The types of things Rick Reed talks about in his talk are standard issue stuff. Lock contention? Okay, how about using an architecture that doesn't require locks in the first place?

With Erlang, you're forced into the Erlang way from day one, and it'll be tough to escape. The good news is that Erlang has a good design overall, so as long as you can modify the engine under the hood, you'll be fine.

I don't think anyone should be scared away from Erlang, just be aware what you're getting into—like any other tech you could deploy.

[Xorlev]

Hard to avoid lock contention when it's happening in the OS.

[erichocean]

Yup, that's why you skip that too:

https://news.ycombinator.com/item?id=7180672