Tech Note 9

NOTE: PathChildrenCache now uses getData() instead of checkExists().

Curator 2.5.0 changes internal behavior for PathChildrenCache. Now, regardless of whether or not "cacheData" is set to true, PathChildrenCache will always call getData on the nodes. This is due to CURATOR-107. It's been shown that using checkExists() with watchers can cause a type of memory leak as watchers will be left dangling on non-existent ZNodes. Calling getData() works around this issue. However, it's possible that this change will affect performance. If you would like the old behavior of using checkExists(), you can set a system property: add -Dcurator-path-children-cache-use-exists=true to your command line or call System.setProperty("curator-path-children-cache-use-exists", "true").

 

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