Details
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Sub-task
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Status: Closed
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Blocker
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Resolution: Done
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None
Description
Speculative execution is introduced in Flink 1.16 to deal with temporary slow tasks caused by slow nodes. This feature currently consists of 4 FLIPs:
- FLIP-168: Speculative Execution core part
- FLIP-224: Blocklist Mechanism
- FLIP-245: Source Supports Speculative Execution
- FLIP-249: Flink Web UI Enhancement for Speculative Execution
This ticket aims for verifying FLIP-168, along with FLIP-224 and FLIP-249.
More details about this feature and how to use it can be found in this documentation.
To do the verification, the process can be:
- Write a Flink job which has a subtask running much slower than others (e.g. sleep indefinitely if it runs on a certain host, the hostname can be retrieved via InetAddress.getLocalHost().getHostName(), or if its (subtaskIndex + attemptNumer) % 2 == 0)
- Modify Flink configuration file to enable speculative execution and tune the configuration as you like
- Submit the job. Checking the web UI, logs, metrics and produced result.