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  1. Hadoop HDFS
  2. HDFS-1073 Simpler model for Namenode's fs Image and edit Logs
  3. HDFS-1994

Fix race conditions when running two rapidly checkpointing 2NNs

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Details

    • Sub-task
    • Status: Resolved
    • Major
    • Resolution: Fixed
    • Edit log branch (HDFS-1073)
    • Edit log branch (HDFS-1073)
    • namenode
    • None
    • Reviewed

    Description

      HDFS-1984 added the ability to run two secondary namenodes at the same time. However, there were two races I found when stress testing this (by running two NNs each checkpointing in a tight loop with no sleep):
      1) the writing of the seen_txid file was not atomic, so it was at some points reading an empty file
      2) it was possible for two checkpointers to try to take a checkpoint at the same transaction ID, which would cause the two image downloads to collide and fail

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            tlipcon Todd Lipcon Assign to me
            tlipcon Todd Lipcon
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