Processes

Execute the app as one or more stateless processes.

• Apps are executed in the execution environment as one or more processes.
  • Might be a single script.
  • Could be many different types of processes, e.g. one-shot through to heavily multi-process processing workloads.
• Processes are stateless and share nothing.
  • Persistence takes place in stateful Backing services.
• Execution environment memory and filesystem resources are brief, single-transaction caches.
  • Never assume anything is cached in memory and available for future transactions.
  • Relocation will mean starting from a cold cache.
  • Transformation of assets should take place in the build stage.
• No reliance on sticky sessions:
  • They're flakey!
  • Store session state in a Cache that supports time-based expiration, and identifiers in HTTP.

References

• VI. Processes

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Backlinks

• The Twelve-Factor App (public)
• Administrative processes (public)
• Concurrency (public)
• Disposability (public)
• Logs (public)