How does fault-tolerant architecture ensure reliability in ChatGPT-scale distributed systems?

Fault-tolerant architecture ensures ChatGPT continues serving requests despite GPU, node, or network failures using redundancy, retries, and graceful degradation.

At large scale, ChatGPT runs on thousands of distributed GPU nodes, making failures inevitable. Fault-tolerant architecture ensures uninterrupted service through redundancy (multiple replicas), health checks, automatic failover, request retries, and graceful degradation strategies.

If a GPU worker fails mid-inference, requests are rerouted to healthy replicas. In some cases, the system may downgrade to a smaller model or partial response mode to maintain availability.…