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Currently, one Flink cluster can only use one shuffle service plugin configured by 'shuffle-service-factory.class'. This is not a problem for per-job cluster, but for session cluster, this is not flexible enough and cannot support use cases like selecting different shuffle service for different workloads (e.g. batch vs. streaming). As discussed in https://lists.apache.org/thread/k4owttq9q3cq4knoobrzc31bghf7vc0o, the community has considered to implement this feature when introducing the pluggable shuffle service abstraction, there are also some relevant followup issues:

Public Interfaces

To Implement this feature, we need to support job level shuffle service configuration. Currently, only cluster level shuffle service configuration is supported by configuring 'shuffle-service-factory.class'. If a user first starts a Flink cluster and then he/she tries to change the shuffle service by reconfiguring 'shuffle-service-factory.class', he/she will fail because per-job level configuration will not passed to runtime so does not take effect currently.

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