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Paths stored in Zookeeper

Wiki MarkupNotation: When an element in a path is denoted \ [xyz\], that means that the value of xyz is not fixed and there is in fact a znode for each possible value of xyz. For example /topics/\[topic\] would be a directory named /topics containing a directory for each topic name. An arrow -> is used to indicate the contents of a znode. For example /hello -> world would indicate a znode /hello containing the value "world". A path is persistent unless it’s marked as ephemeral.

We store the following paths in Zookeeper:

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1. Partition-reassigned listener:
   1. child change on /brokers/partitions_reassignedunmigrated-wiki-markup
   2. child change on /brokers/partitions_reassigned/\[topic\]

Zookeeper listeners on all brokers

1. 1. Wiki MarkupLeader-change listener: value change on /brokers/topics/\[topic\]/\[partition_id\]/leaderunmigrated-wiki-markup
   2. State-change listener: child change on /brokers/state/\[broker_id\]

Configuration parameters

1. 1. LeaderElectionWaitTime: controls the maximum amount of time that we wait during leader election.
   2. KeepInSyncTime: controls the maximum amount of time that a leader waits before dropping a follower from the in-sync replica set.

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