Task vs DAG vs Run for Retries

Concepts covered: paTaskDagRun, paLogicalDate

Three words appear in every conversation about orchestration: task, DAG, and run. New engineers use the three interchangeably, and most of the time the imprecision does not bite. It bites hard when retry semantics are at stake, because the orchestrator retries at exactly one of those three levels and the answer matters. The vocabulary below is precise on purpose. The Three Words Retries Happen at the Task Instance Level When an orchestrator retries a failure, it retries a task instance. It does not retry the task in the abstract, because the task is a definition, not a running thing. It does not retry the DAG, because the DAG is the structure of work, not a running thing either. It retries this task in this run on this date with these inputs. That precision is what makes idempotency possib

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