Thesharing opened a new pull request #16436:
URL: https://github.com/apache/flink/pull/16436


   ## What is the purpose of the change
   
   *In FLINK-22017, we construct a scenario that regions may never be scheduled 
when there is cross-region blocking edges in the graph. To solve this issue we 
should allow BLOCKING result partitions be consumable individually. Note that 
this will result in the scheduling to become execution-vertex-wise instead of 
stage-wise, with a nice side effect towards better resource utilization. The 
PipelinedRegionSchedulingStrategy can be simplified along with change to get 
rid of the correlatedResultPartitions.*
   
   *There's three main concerns that need to be considered:*
   
   *1. Since scheduling become execution-vertex-wise instead of stage-wise, we 
need to make sure the computation complexity in 
PipelinedRegionSchedulingStrategy won't fall back to O(n^2). We tested it with 
benchmark and end-to-end tests. Our pull request doesn't introduce significant 
performance regression.*
   
   *2. Before this pull request,`finishPartitionsAndUpdateConsumers` already 
has the complexity of O(n^2). We intend to optimize it in FLINK-21915. Since 
each partition will finish individually, this optimization is not valid any 
more. As we tested in the job with two vertices (parallelism 8k, all-to-all, 
batch mode), it takes less than five seconds.*
   
   *3. `SchedulingDownstreamTasksInBatchJobBenchmark` is modified in accordance 
with this change. We need to monitor the result of this benchmark.*
   
   ## Brief change log
   
     - *We can get the ConsumedPartitionGroup that an 
IntermediateResultPartition or a DefaultResultPartition belongs to*
     - *A blocking result partition will be consumable individually once its 
producer is finished. It doesn't need to wait until all other 
IntermediateResultPartitions that belong to the same IntermediateResult finish*
   
   ## Verifying this change
   
   This change added tests and can be verified as follows:
   
     - *Added unit tests for getting ConsumedPartitionGroup from 
IntermediateResultPartition and DefaultResultPartition*
     - *Added unit tests for scheduling pointwise vertices in the batch job*
     - *Extended the unit tests that schedule vertices in the graph illustrated 
in FLINK-22017*
     - *Manually verified the change by running a job with two job vertices, 
their parallelisms are both 8k. Two distribution patterns (pointwise and 
all-to-all) and two job type (batch and streaming) are involved. All jobs 
finish correctly.*
   
   ## Does this pull request potentially affect one of the following parts:
   
     - Dependencies (does it add or upgrade a dependency): (yes / **no**)
     - The public API, i.e., is any changed class annotated with 
`@Public(Evolving)`: (yes / **no**)
     - The serializers: (yes / **no** / don't know)
     - The runtime per-record code paths (performance sensitive): (yes / **no** 
/ don't know)
     - Anything that affects deployment or recovery: JobManager (and its 
components), Checkpointing, Kubernetes/Yarn, ZooKeeper: (**yes** / no / don't 
know)
     - The S3 file system connector: (yes / **no** / don't know)
   
   ## Documentation
   
     - Does this pull request introduce a new feature? (yes / **no**)
     - If yes, how is the feature documented? (**not applicable** / docs / 
JavaDocs / not documented)
   


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