BREAKDOWN OF HDFS-7285 SUBTASKS AND RELATED JIRAS

    HDFS-7347. Configurable erasure coding policy for individual files and
    directories ( Zhe Zhang via vinayakumarb )

    HDFS-7339. Representing striped block groups in NameNode with hierarchical
    naming protocol ( Zhe Zhang )

    HDFS-7652. Process block reports for erasure coded blocks (Zhe Zhang)

    HDFS-7716. Erasure Coding: extend BlockInfo to handle EC info (Jing Zhao)

    HDFS-7749. Erasure Coding: Add striped block support in INodeFile (Jing Zhao)

    HDFS-7837. Erasure Coding: allocate and persist striped blocks in NameNode
    (Jing Zhao via Zhe Zhang)

    HDFS-7872. Erasure Coding: INodeFile.dumpTreeRecursively() supports to print
    striped blocks (Takuya Fukudome via jing9)

    HDFS-7853. Erasure coding: extend LocatedBlocks to support reading from
    striped files (Jing Zhao)

    HDFS-7826. Erasure Coding: Update INodeFile quota computation for striped
    blocks ( Kai Sasaki via jing9 )

    HDFS-7912. Erasure Coding: track BlockInfo instead of Block in
    UnderReplicatedBlocks and PendingReplicationBlocks (Jing Zhao)

    HDFS-7369. Erasure coding: distribute recovery work for striped blocks to
    DataNode (Zhe Zhang)

    HDFS-7864. Erasure Coding: Update safemode calculation for striped blocks
    (GAO Rui via jing9)

    HDFS-7827. Erasure Coding: support striped blocks in non-protobuf fsimage
    ( Hui Zheng via jing9 )

    HDFS-7616. Add a test for BlockGroup support in FSImage.
    (Takuya Fukudome via szetszwo)

    HDFS-7907. Erasure Coding: track invalid, corrupt, and under-recovery striped
    blocks in NameNode (Jing Zhao)

    HDFS-8005. Erasure Coding: simplify striped block recovery work computation
    and add tests (Jing Zhao)

    HDFS-7617. Add unit tests for editlog transactions for EC 
    (Hui Zheng via Zhe Zhang)

    HDFS-7839. Erasure coding: implement facilities in NameNode to create and
    manage EC zones (Zhe Zhang)

    HDFS-8023. Erasure Coding: retrieve eraure coding schema for a file from
    NameNode (vinayakumarb)
    
    HDFS-8074. Define a system-wide default EC schema. (Kai Zheng)

    HDFS-8104. Make hard-coded values consistent with the system default schema first before remove them. (Kai Zheng)

    HDFS-7889. Subclass DFSOutputStream to support writing striping layout files. (Li Bo via Kai Zheng)