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Varun Saxena commented on YARN-2946: ------------------------------------ Frankly, as all of these methods *merely have a single line calling another method* in {{ZKRMStateStore}}, in addition to call to isFencedState and notifyStoreOperationFailed. Hence, we *do not even need a synchronized block* in these methods in RMStateStore. Just make the relevant method in ZKRMStateStore *synchronized*. > DeadLock's in RMStateStore<->ZKRMStateStore > ------------------------------------------- > > Key: YARN-2946 > URL: https://issues.apache.org/jira/browse/YARN-2946 > Project: Hadoop YARN > Issue Type: Bug > Components: resourcemanager > Affects Versions: 2.7.0 > Reporter: Rohith > Assignee: Rohith > Priority: Blocker > Attachments: 0001-YARN-2946.patch, 0002-YARN-2946.patch, > TestYARN2946.java > > > Found one deadlock in ZKRMStateStore. > # Initial stage zkClient is null because of zk disconnected event. > # When ZKRMstatestore#runWithCheck() wait(zkSessionTimeout) for zkClient to > re establish zookeeper connection either via synconnected or expired event, > it is highly possible that any other thred can obtain lock on > {{ZKRMStateStore.this}} from state machine transition events. This cause > Deadlock in ZKRMStateStore. -- This message was sent by Atlassian JIRA (v6.3.4#6332)