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  1. Hadoop HDFS
  2. HDFS-5074

Allow starting up from an fsimage checkpoint in the middle of a segment

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    Details

    • Type: Bug
    • Status: Closed
    • Priority: Major
    • Resolution: Fixed
    • Affects Version/s: 2.1.0-beta, 3.0.0-alpha1
    • Fix Version/s: 2.3.0
    • Component/s: ha, namenode
    • Labels:
      None
    • Target Version/s:
    • Hadoop Flags:
      Reviewed

      Description

      We've seen the following behavior a couple times:

      • SBN is running and somehow encounters an error in the middle of replaying an edit log in the tailer (eg the JN it's reading from crashes)
      • SBN successfully has processed half of the edits in the segment it was reading.
      • SBN saves a checkpoint, which now falls in the middle of a segment, and then restarts

      Upon restart, the SBN will load this checkpoint which falls in the middle of a segment. selectInputStreams then fails when the SBN requests a mid-segment txid.

      We should handle this case by downloading the right segment and fast-forwarding to the correct txid.

        Attachments

        1. hdfs-5074.txt
          51 kB
          Todd Lipcon
        2. hdfs-5074.txt
          48 kB
          Todd Lipcon

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              • Assignee:
                tlipcon Todd Lipcon
                Reporter:
                tlipcon Todd Lipcon
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                • Created:
                  Updated:
                  Resolved: