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  1. Hadoop Common
  2. HADOOP-14831 Über-jira: S3a phase IV: Hadoop 3.1 features
  3. HADOOP-13282

S3 blob etags to be made visible in S3A status/getFileChecksum() calls

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Details

    • Sub-task
    • Status: Resolved
    • Minor
    • Resolution: Fixed
    • 2.9.0
    • 3.1.0
    • fs/s3
    • None
    • Incompatible change
    • Hide
      now that S3A has a checksum, you need to explicitly disable checksums when uploading from HDFS : use -skipCrc

      checksum verification does work between s3a buckets, provided the block size on uploads was identical
      Show
      now that S3A has a checksum, you need to explicitly disable checksums when uploading from HDFS : use -skipCrc checksum verification does work between s3a buckets, provided the block size on uploads was identical

    Description

      If the etags of blobs were exported via getFileChecksum(), it'd be possible to probe for a blob being in sync with a local file. Distcp could use this to decide whether to skip a file or not.

      Now, there's a problem there: distcp needs source and dest filesystems to implement the same algorithm. It'd only work out the box if you were copying between S3 instances. There are also quirks with encryption and multipart: s3 docs. At the very least, it's something which could be used when indexing the FS, to check for changes later.

      Attachments

        1. HADOOP-13282-001.patch
          4 kB
          Steve Loughran
        2. HADOOP-13282-002.patch
          16 kB
          Steve Loughran
        3. HADOOP-13282-003.patch
          16 kB
          Steve Loughran
        4. HADOOP-13282-004.patch
          16 kB
          Steve Loughran

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              stevel@apache.org Steve Loughran
              stevel@apache.org Steve Loughran
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                Created:
                Updated:
                Resolved: