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  1. Hadoop Common
  2. HADOOP-3677

Problems with generation stamp upgrade

    Details

    • Type: Bug
    • Status: Closed
    • Priority: Blocker
    • Resolution: Fixed
    • Affects Version/s: 0.18.0
    • Fix Version/s: 0.18.0
    • Component/s: None
    • Labels:
      None
    • Release Note:
      Simplify generation stamp upgrade by making is a local upgrade on datandodes. Deleted distributed upgrade.

      Description

      1. The generation stamp upgrade renames blocks' meta-files so that the name contains the block generation stamp as stated in HADOOP-2656.
        If a data-node has blocks that do not belong to any files and the name-node asks the data-node to remove those blocks
        during or before the upgrade started the data-node will remove the blocks but not the meta-files because their names
        are still in the old format which is not recognized by the new code. So we can end up with a number of garbage files which
        will be hard to recognize that they are unused and the system will never remove them automatically.
        I think this should be handled by the upgrade code in the end, but may be it will be right to fix HADOOP-3002 for the 0.18 release,
        which will avoid scheduling block removal when the name-node is in safe-mode.
      2. I was not able to get the upgrade -force option to work. This option lets the name-node proceed with a distributed upgrade even if
        the data-nodes are not able to complete their local upgrades. Did we test this feature at all for the generation stamp upgrade?

        Attachments

        1. HADOOP-3677-trunk.patch
          44 kB
          Raghu Angadi
        2. HADOOP-3677-branch-018.patch
          39 kB
          Raghu Angadi
        3. HADOOP-3677-trunk.patch
          5 kB
          Raghu Angadi

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              • Assignee:
                rangadi Raghu Angadi
                Reporter:
                shv Konstantin Shvachko
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                Dates

                • Created:
                  Updated:
                  Resolved: