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ASF GitHub Bot commented on STORM-837: -------------------------------------- Github user arunmahadevan commented on the pull request: https://github.com/apache/storm/pull/644#issuecomment-127146640 Hi @harshach, added a note to storm hdfs README.md and modified code to disable exactly once based on file size as well. > HdfsState ignores commits > ------------------------- > > Key: STORM-837 > URL: https://issues.apache.org/jira/browse/STORM-837 > Project: Apache Storm > Issue Type: Bug > Reporter: Robert Joseph Evans > Assignee: Arun Mahadevan > Priority: Critical > > HdfsState works with trident which is supposed to provide exactly once > processing. It does this two ways, first by informing the state about > commits so it can be sure the data is written out, and second by having a > commit id, so that double commits can be handled. > HdfsState ignores the beginCommit and commit calls, and with that ignores the > ids. This means that if you use HdfsState and your worker crashes you may > both lose data and get some data twice. > At a minimum the flush and file rotation should be tied to the commit in some > way. The commit ID should at a minimum be written out with the data so > someone reading the data can have a hope of deduping it themselves. > Also with the rotationActions it is possible for a file that was partially > written is leaked, and never moved to the final location, because it is not > rotated. I personally think the actions are too generic for this case and > need to be deprecated. -- This message was sent by Atlassian JIRA (v6.3.4#6332)