[FLINK-8807] ZookeeperCompleted checkpoint store can get stuck in infinite loop

• Type: Bug
• Status: Closed
• Priority: Blocker
• Resolution: Fixed
• Affects Version/s: 1.5.0
• Fix Version/s: 1.3.3, 1.5.0, 1.4.3
• Component/s: State Backends, Checkpointing
• Assignee: Aljoscha Krettek
• Reporter: Aljoscha Krettek
• Created: 28/Feb/18 11:26
• Updated: 12/Mar/18 15:55
• Resolved: 12/Mar/18 15:55

Description

This code: https://github.com/apache/flink/blob/9071e3befb8c279f73c3094c9f6bddc0e7cce9e5/flink-runtime/src/main/java/org/apache/flink/runtime/checkpoint/ZooKeeperCompletedCheckpointStore.java#L201 can be stuck forever if at least one checkpoint is not readable because CompletedCheckpoint does not have a proper equals()/hashCode() anymore.

We have to fix this and also add a unit test that verifies the loop still works if we make one snapshot unreadable.

Issue Links

• links to: GitHub Pull Request #5623