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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

    • Bug
    • Status: Closed
    • Major
    • Resolution: Fixed
    • 2.1.0-beta, 3.0.0-alpha1
    • 2.3.0
    • ha, namenode
    • None
    • 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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              tlipcon Todd Lipcon
              tlipcon Todd Lipcon
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              Dates

                Created:
                Updated:
                Resolved: