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Todd Lipcon commented on HDFS-3863: ----------------------------------- Hi Chao. Really interesting idea. Thanks! Let me try to code it up and see how it works. > QJM: track last "committed" txid > -------------------------------- > > Key: HDFS-3863 > URL: https://issues.apache.org/jira/browse/HDFS-3863 > Project: Hadoop HDFS > Issue Type: Sub-task > Components: ha > Affects Versions: QuorumJournalManager (HDFS-3077) > Reporter: Todd Lipcon > Assignee: Todd Lipcon > > Per some discussion with [~stepinto] > [here|https://issues.apache.org/jira/browse/HDFS-3077?focusedCommentId=13422579&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-13422579], > we should keep track of the "last committed txid" on each JournalNode. Then > during any recovery operation, we can sanity-check that we aren't asked to > truncate a log to an earlier transaction. > This is also a necessary step if we want to support reading from in-progress > segments in the future (since we should only allow reads up to the commit > point) -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators For more information on JIRA, see: http://www.atlassian.com/software/jira