Shammon created FLINK-25055:
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             Summary: Support listen and notify mechanism for PartitionRequest
                 Key: FLINK-25055
                 URL: https://issues.apache.org/jira/browse/FLINK-25055
             Project: Flink
          Issue Type: Improvement
          Components: Runtime / Network
    Affects Versions: 1.13.3, 1.12.5, 1.14.0
            Reporter: Shammon


We submit batch jobs to flink session cluster with eager scheduler for olap. JM 
deploys subtasks to TaskManager independently, and the downstream subtasks may 
start before the upstream ones are not ready. The downstream subtask sends 
PartitionRequest to upstream ones, and may receive PartitionNotFoundException 
from them. Then it will retry to send PartitionRequest after a few ms until 
timeout.

The current approach raises two problems. First, there will be too many retry 
PartitionRequest messages. Each downstream subtask will send PartitionRequest 
to all its upstream subtasks and the total number of messages will be O(N*N), 
where N is the parallelism of subtasks. Secondly, the interval between polling 
retries will increase the delay for upstream and downstream tasks to confirm 
PartitionRequest.

We want to support listen and notify mechanism for PartitionRequest when the 
job needs no failover. Upstream TaskManager will add the PartitionRequest to a 
listen list with a timeout checker, and notify the request when the task 
register its partition in the TaskManager.

[~nkubicek] I noticed that your scenario of using flink is similar to ours. 
What do you think?  And hope to hear from you [~trohrmann] THX



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