davidradl commented on code in PR #28863: URL: https://github.com/apache/flink/pull/28863#discussion_r3871974522
########## docs/content/docs/concepts/glossary.md: ########## @@ -94,143 +169,362 @@ the same [Operator](#operator) or [Function](#function) type are running in para #### Flink Job -A Flink Job is the runtime representation of a [logical graph](#logical-graph) -(also often called dataflow graph) that is created and submitted by calling -`execute()` in a [Flink Application](#flink-application). +A Flink Job is the unit of data processing execution in Flink: a Job as a whole is submitted, +started, stopped and resumed, although under some conditions Flink may restart a Job only partially. + +A Job is submitted either by a [Flink Application](#flink-application), by calling `execute()` on an +execution environment, or as a single [Flink SQL Statement](#flink-sql-statement) or [Statement +Set](#statement-set). + +A Flink Job is the runtime representation of a [Logical Graph](#logical-graph) (also often called +*Dataflow Graph*). The Logical Graph is optimized into a [Job Graph](#job-graph), from which the +[Physical Graph](#physical-graph) that actually runs in a [Flink Cluster](#flink-cluster) is derived. #### Flink Job Cluster A Flink Job Cluster is a dedicated [Flink Cluster](#flink-cluster) that only executes a single [Flink Job](#flink-job). The lifetime of the -[Flink Cluster](#flink-cluster) is bound to the lifetime of the Flink Job. -This deployment mode has been deprecated since Flink 1.15. +[Flink Cluster](#flink-cluster) is bound to the lifetime of the Flink Job. +This deployment mode has been deprecated since Flink 1.15. + +#### Job Graph + +Also *JobGraph*. -#### JobGraph +A Job Graph is the optimized representation of a [Logical Graph](#logical-graph), and the +representation that a [Flink Application](#flink-application) submits to the [Flink +Cluster](#flink-cluster). -see [Logical Graph](#logical-graph) +Producing the Job Graph is mainly a matter of chaining: consecutive [Operators](#operator) that are +not separated by a repartitioning are merged into a single [Task](#task). The nodes of a Job Graph +are therefore [Tasks](#task), each implementing one Operator or one [Operator +Chain](#operator-chain). + +The Job Graph is translated into a [Physical Graph](#physical-graph) for execution. + +Job Graph is sometimes referred to as *Optimized Dataflow*. #### Flink JobManager -The JobManager is the orchestrator of a [Flink Cluster](#flink-cluster). It contains three distinct -components: Flink Resource Manager, Flink Dispatcher and one [Flink JobMaster](#flink-jobmaster) -per running [Flink Job](#flink-job). +Also *Job Manager*. + +The JobManager is the orchestrator of a [Flink Cluster](#flink-cluster). It does not process any +data itself: it translates the submitted [Job Graph](#job-graph) into a [Physical +Graph](#physical-graph), schedules the resulting [Sub-Tasks](#sub-task) on the +[TaskManagers](#flink-taskmanager), and coordinates [Checkpoints](#checkpoint) and +[Savepoints](#savepoint). It contains three distinct components: Flink Resource Manager, Flink +Dispatcher and one [Flink JobMaster](#flink-jobmaster) per running [Flink Job](#flink-job). Review Comment: link to a picture? -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
