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Fengnan Li commented on HDFS-15383: ----------------------------------- Thanks! [~elgoiri] [~hexiaoqiao] > RBF: Disable watch in ZKDelegationSecretManager for performance > --------------------------------------------------------------- > > Key: HDFS-15383 > URL: https://issues.apache.org/jira/browse/HDFS-15383 > Project: Hadoop HDFS > Issue Type: Improvement > Reporter: Fengnan Li > Assignee: Fengnan Li > Priority: Major > Fix For: 3.4.0 > > > Based on the current design for delegation token in secure Router, the total > number of watches for tokens is the product of number of routers and number > of tokens, this is due to ZKDelegationTokenManager is using PathChildrenCache > from curator, which automatically sets the watch and ZK will push the sync > information to each router. There are some evaluations about the number of > watches in Zookeeper has negative performance impact to Zookeeper server. > In our practice when the number of watches exceeds 1.2 Million in a single ZK > server there will be significant ZK performance degradation. Thus this ticket > is to rewrite ZKDelegationTokenManagerImpl.java to explicitly disable the > PathChildrenCache and have Routers sync periodically from Zookeeper. This has > been working fine at the scale of 10 Routers with 2 million tokens. -- This message was sent by Atlassian Jira (v8.3.4#803005) --------------------------------------------------------------------- To unsubscribe, e-mail: hdfs-issues-unsubscr...@hadoop.apache.org For additional commands, e-mail: hdfs-issues-h...@hadoop.apache.org