Hadoop HDFS
  1. Hadoop HDFS
  2. HDFS-2379

0.20: Allow block reports to proceed without holding FSDataset lock

    Details

    • Type: Bug Bug
    • Status: Closed
    • Priority: Critical Critical
    • Resolution: Fixed
    • Affects Version/s: 1.0.0
    • Fix Version/s: 1.0.1
    • Component/s: datanode
    • Labels:
      None
    • Hadoop Flags:
      Reviewed

      Description

      As disks are getting larger and more plentiful, we're seeing DNs with multiple millions of blocks on a single machine. When page cache space is tight, block reports can take multiple minutes to generate. Currently, during the scanning of the data directories to generate a report, the FSVolumeSet lock is held. This causes writes and reads to block, timeout, etc, causing big problems especially for clients like HBase.

      This JIRA is to explore some of the ideas originally discussed in HADOOP-4584 for the 0.20.20x series.

      1. hdfs-2379.txt
        32 kB
        Todd Lipcon
      2. hdfs-2379.txt
        32 kB
        Todd Lipcon
      3. hdfs-2379.txt
        32 kB
        Todd Lipcon
      4. hdfs-2379.txt
        32 kB
        Todd Lipcon
      5. hdfs-2379.txt
        31 kB
        Todd Lipcon
      6. hdfs-2379.txt
        11 kB
        Todd Lipcon

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

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