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  1. Hadoop HDFS
  2. HDFS-895

Allow hflush/sync to occur in parallel with new writes to the file

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    • Hadoop Flags:
      Reviewed

      Description

      In the current trunk, the HDFS client methods writeChunk() and hflush./sync are syncronized. This means that if a hflush/sync is in progress, an applicationn cannot write data to the HDFS client buffer. This reduces the write throughput of the transaction log in HBase.

      The hflush/sync should allow new writes to happen to the HDFS client even when a hflush/sync is in progress. It can record the seqno of the message for which it should receice the ack, indicate to the DataStream thread to star flushing those messages, exit the synchronized section and just wai for that ack to arrive.

        Attachments

        1. 895-delta-for-review.txt
          7 kB
          Todd Lipcon
        2. ASF.LICENSE.NOT.GRANTED--hdfs-895.txt
          15 kB
          Todd Lipcon
        3. ASF.LICENSE.NOT.GRANTED--hdfs-895-trunk.txt
          19 kB
          Todd Lipcon
        4. HDFS-895.20-security.1.patch
          18 kB
          Jitendra Nath Pandey
        5. hdfs-895.txt
          22 kB
          Todd Lipcon
        6. hdfs-895.txt
          21 kB
          Todd Lipcon
        7. hdfs-895.txt
          22 kB
          Todd Lipcon
        8. hdfs-895.txt
          22 kB
          Todd Lipcon
        9. hdfs-895.txt
          21 kB
          Todd Lipcon
        10. hdfs-895.txt
          17 kB
          Todd Lipcon
        11. hdfs-895-0.20-append.txt
          19 kB
          Todd Lipcon
        12. hdfs-895-0.20-append.txt
          16 kB
          Todd Lipcon
        13. hdfs-895-20.txt
          16 kB
          Todd Lipcon
        14. hdfs-895-branch-20-append.txt
          17 kB
          Todd Lipcon
        15. hdfs-895-ontopof-1497.txt
          23 kB
          Todd Lipcon
        16. hdfs-895-review.txt
          20 kB
          Todd Lipcon

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              • Assignee:
                tlipcon Todd Lipcon
                Reporter:
                dhruba dhruba borthakur
              • Votes:
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                Dates

                • Created:
                  Updated:
                  Resolved: