Uploaded image for project: 'Hadoop HDFS'
  1. Hadoop HDFS
  2. HDFS-7955

Improve naming of classes, methods, and variables related to block replication and recovery

    XMLWordPrintableJSON

Details

    • Improvement
    • Status: Resolved
    • Major
    • Resolution: Fixed
    • None
    • None
    • erasure-coding
    • None

    Description

      Many existing names should be revised to avoid confusion when blocks can be both replicated and erasure coded. This JIRA aims to solicit opinions on making those names more consistent and intuitive.

      1. In current HDFS block recovery refers to the process of finalizing the last block of a file, triggered by lease recovery. It is different from the intuitive meaning of recovering a lost block. To avoid confusion, I can think of 2 options:
        • Rename this process as block finalization or block completion. I prefer this option because this is literally not a recovery.
        • If we want to keep existing terms unchanged we can name all EC recovery and re-replication logics as reconstruction.
      2. As Kai suggested under HDFS-7369, several replication-based names should be made more generic:
        • UnderReplicatedBlocks and neededReplications. E.g. we can use LowRedundancyBlocks/AtRiskBlocks, and neededRecovery/neededReconstruction.
        • PendingReplicationBlocks
        • ReplicationMonitor

      I'm sure the above list is incomplete; discussions and comments are very welcome.

      Attachments

        1. HDFS-7955-001.patch
          106 kB
          Rakesh Radhakrishnan
        2. HDFS-7955-002.patch
          77 kB
          Rakesh Radhakrishnan
        3. HDFS-7955-003.patch
          123 kB
          Rakesh Radhakrishnan
        4. HDFS-7955-004.patch
          127 kB
          Rakesh Radhakrishnan
        5. HDFS-7955-5.patch
          120 kB
          Rakesh Radhakrishnan

        Issue Links

          Activity

            People

              rakeshr Rakesh Radhakrishnan
              zhz Zhe Zhang
              Votes:
              0 Vote for this issue
              Watchers:
              10 Start watching this issue

              Dates

                Created:
                Updated:
                Resolved: