[DRILL-4888] putIfAbsent for ZK stores is not atomic

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.8.0
• Fix Version/s: 1.9.0
• Assignee: Arina Ielchiieva
• Reporter: Arina Ielchiieva
• Created: 13/Sep/16 17:29
• Updated: 01/Dec/16 11:07
• Resolved: 01/Dec/16 10:51

Description

putIfAbsent method in ZookeeperPersistentStore [1] and ZkEphemeralStore [2] is not atomic. First is checks if znode is absent and then puts data into it, but by that time someone might have created znode.

[1] https://github.com/apache/drill/blob/master/exec/java-exec/src/main/java/org/apache/drill/exec/store/sys/store/ZookeeperPersistentStore.java#L89

[2] https://github.com/apache/drill/blob/master/exec/java-exec/src/main/java/org/apache/drill/exec/coord/zk/ZkEphemeralStore.java#L90

Issue Links

• relates to: DRILL-4726 Dynamic UDFs support