Self-hosted n8n has a failure mode almost everyone hits eventually: everything runs fine for months, then one day the editor won't load, webhooks time out, and workflows silently stop. It's rarely a mystery when you dig in — it's almost always one of two things:
Single-instance execution. By default, n8n executes workflows in the same process that serves the UI and receives webhooks. One heavy execution (a big loop, an AI agent chain, a large file) and everything else starves.
The unbounded executions table. Every run writes execution data to your database. With no pruning, the table grows until Postgres becomes the bottleneck — or the disk fills.
Both have first-class fixes in n8n itself. They're just not the defaults. This post walks through the production setup n8n's own docs recommend — queue mode — plus the hardening settings that prevent the slow-motion failures.
How queue mode works
