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  1. Hadoop HDFS
  2. HDFS-942

Read and write metrics misleading/not helpful

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Details

    • Bug
    • Status: Open
    • Major
    • Resolution: Unresolved
    • 0.22.0
    • None
    • datanode
    • None

    Description

      the metrics wrap the entire readBlock() writeBlock() call (in DataXciever#run())

      The problem with this is it includes the client socket read/write time. This means if a client is slow at streaming a write block (eg: in hbase) then it skews the write metrics and makes it look like the server is really slow. Same problem with reads.

      It would be nice if reads/writes meant actually local disk io and related processing (eg: checksum verification/generation)

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              Unassigned Unassigned
              ryanobjc ryan rawson
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              Dates

                Created:
                Updated: