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  1. Hadoop Common
  2. HADOOP-11794

Enable distcp to copy blocks in parallel

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Details

    • Improvement
    • Status: Resolved
    • Major
    • Resolution: Fixed
    • 0.21.0
    • 2.9.0, 3.0.0-alpha4
    • tools/distcp
    • None
    • Reviewed
    • Hide
      If a positive value is passed to command line switch -blocksperchunk, files with more blocks than this value will be split into chunks of `<blocksperchunk>` blocks to be transferred in parallel, and reassembled on the destination. By default, `<blocksperchunk>` is 0 and the files will be transmitted in their entirety without splitting. This switch is only applicable when both the source file system supports getBlockLocations and target supports concat.
      Show
      If a positive value is passed to command line switch -blocksperchunk, files with more blocks than this value will be split into chunks of `<blocksperchunk>` blocks to be transferred in parallel, and reassembled on the destination. By default, `<blocksperchunk>` is 0 and the files will be transmitted in their entirety without splitting. This switch is only applicable when both the source file system supports getBlockLocations and target supports concat.

    Description

      The minimum unit of work for a distcp task is a file. We have files that are greater than 1 TB with a block size of 1 GB. If we use distcp to copy these files, the tasks either take a long long long time or finally fails. A better way for distcp would be to copy all the source blocks in parallel, and then stich the blocks back to files at the destination via the HDFS Concat API (HDFS-222)

      Attachments

        1. MAPREDUCE-2257.patch
          62 kB
          Rosie Li
        2. HADOOP-11794.001.patch
          52 kB
          Yongjun Zhang
        3. HADOOP-11794.002.patch
          58 kB
          Yongjun Zhang
        4. HADOOP-11794.003.patch
          61 kB
          Yongjun Zhang
        5. HADOOP-11794.004.patch
          62 kB
          Yongjun Zhang
        6. HADOOP-11794.005.patch
          62 kB
          Yongjun Zhang
        7. HADOOP-11794.006.patch
          63 kB
          Yongjun Zhang
        8. HADOOP-11794.007.patch
          70 kB
          Yongjun Zhang
        9. HADOOP-11794.008.patch
          70 kB
          Yongjun Zhang
        10. HADOOP-11794.009.patch
          70 kB
          Yongjun Zhang
        11. HADOOP-11794.010.patch
          70 kB
          Yongjun Zhang
        12. HADOOP-11794.010.branch2.patch
          70 kB
          Yongjun Zhang
        13. HADOOP-11794.010.branch2.002.patch
          71 kB
          Yongjun Zhang

        Issue Links

          blocks

          Bug - A problem which impairs or prevents the functions of the product. HDFS-1776 Bug in Concat code

          • Major - Major loss of function.
          • Closed
          causes

          Bug - A problem which impairs or prevents the functions of the product. HADOOP-15850 CopyCommitter#concatFileChunks should check that the blocks per chunk is not 0

          • Critical - Crashes, loss of data, severe memory leak.
          • Resolved

          Bug - A problem which impairs or prevents the functions of the product. HADOOP-17611 Distcp parallel file copy breaks the modification time

          • Major - Major loss of function.
          • Patch Available
          is related to

          New Feature - A new feature of the product, which has yet to be developed. HDFS-222 Support for concatenating of files into a single file

          • Major - Major loss of function.
          • Closed

          Improvement - An improvement or enhancement to an existing feature or task. HADOOP-14764 Über-jira adl:// Azure Data Lake Phase II: Performance, Resilience and Testing

          • Major - Major loss of function.
          • Resolved

          Improvement - An improvement or enhancement to an existing feature or task. HADOOP-14866 Backport implementation of parallel block copy in Distcp to hadoop 2.8

          • Major - Major loss of function.
          • Resolved
          relates to

          Bug - A problem which impairs or prevents the functions of the product. HADOOP-16018 DistCp won't reassemble chunks when blocks per chunk > 0

          • Major - Major loss of function.
          • Resolved

          Bug - A problem which impairs or prevents the functions of the product. HADOOP-16049 DistCp result has data and checksum mismatch when blocks per chunk > 0

          • Major - Major loss of function.
          • Resolved

          Improvement - An improvement or enhancement to an existing feature or task. HADOOP-16158 DistCp to support checksum validation when copy blocks in parallel

          • Major - Major loss of function.
          • Resolved

          Activity

            People

              yzhangal Yongjun Zhang
              dhruba Dhruba Borthakur
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              Dates

                Created:
                Updated:
                Resolved: