You could tinker with :max_restarts/:max_seconds on supervisors, but depending on the tree depth that might not be the most efficient way to go about this. You could also put a process elsewhere in the system, which monitors our “critical” process and if it receives an exit message does System.stop(…).

Looks like that it’s maybe time to switch to a NIF-based JSON parser and/or use a streaming one? Options:

• GitHub - rusterlium/juicy: A fast JSON parser for Elixir with some extra features · GitHub (last updated 5 years ago though)
• GitHub - talentdeficit/jsx: an erlang application for consuming, producing and manipulating json. inspired by yajl · GitHub (last updated ~11 months ago, Erlang)
• GitHub - kbrw/json_stream: Small but useful wrapper above erlang `jsx` to stream json elements from an Elixir binary stream. · GitHub (based on the above jsx but last updated 2 years ago)

IMO when you get to the point of a worker timing out due to having to process huge input, a streaming parser is your only viable option. But maybe jiffy or jsonrs would do the job because they should parse several times faster.

I am not sure OTP can help you a lot here; or if you really want that and don’t want to switch the JSON parsing library then maybe extract out the JSON parsing code into a separate app.

While there is a application supervision tree, it likely works differently than you expect. The pid returned from Application.start/2 callback is never restarted. When it crashes the application is considered failed and stopped. Restarts essentially only happen to children of supervisors you control – there’s no implicit supervisor restarting things at the application level.

So you could probably do a setup like this:

        ┌───────────┐
        │  RootSup  │ Allow no restarts
        └───────────┘
              │
      ┌───────┴──────┐
      │              │
      ▼              ▼
┌ ─ ─ ─ ─ ─ ┐  ┌───────────┐
   ImpProc     │  ApplSup  │ Default restart limits
└ ─ ─ ─ ─ ─ ┘  └───────────┘
                     │
               ┌─────┴────────┐
               │              │
               ▼              ▼
         ┌ ─ ─ ─ ─ ─    ┌ ─ ─ ─ ─ ─
             Rest   │       Rest   │
         └ ─ ─ ─ ─ ─    └ ─ ─ ─ ─ ─

There’s also a :significant setting for OTP, which I’m not sure if you can use it yet with elixir: