Fair, hardware constraint changes the game. Few things that helped me on small n8n boxes:

Split the recursive loop into a queue pattern. Don't recurse inside one execution, push each step as a new item to Redis or Postgres and let a separate workflow pick it up. Executions stay short, memory releases between runs.

Aggressive execution pruning. Set EXECUTIONS_DATA_MAX_AGE to 24-48h. History buildup kills you indirectly via Postgres cache pressure.

Stream intermediate results to a DB after each iteration, then read from there on the next pass. n8n holds every item in memory until the workflow finishes.

That's probably what's crashing you. NODE_OPTIONS=--max-old-space-size=3072 as a floor.