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  1. Hadoop HDFS
  2. HDFS-7285 Erasure Coding Support inside HDFS
  3. HDFS-8731

Erasure coding: For a small file missing and under replicated ec-block calculation is incorrect

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    • Type: Sub-task
    • Status: Resolved
    • Priority: Major
    • Resolution: Duplicate
    • Affects Version/s: None
    • Fix Version/s: None
    • Component/s: None
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      Description

      Write a small file (whose replica detail would be : one data replica and 3 parity replicas .)

      Now :
      totalReplicasPerBlock = 4
      targetFileReplication = 9 (calculated based on default RS-6-3 schema)

      Hence the small file ec-blocks is calculated as always missing and underreplicated. which is wrong...

      targetFileReplication = (short) (ecSchema.getNumDataUnits() + ecSchema.getNumParityUnits());
      
            // count missing replicas / under replicated blocks
            if (totalReplicasPerBlock < targetFileReplication && totalReplicasPerBlock > 0) {
              res.missingReplicas += (targetFileReplication - totalReplicasPerBlock);
      	res.numUnderReplicatedBlocks += 1;
      

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              • Assignee:
                andreina J.Andreina
                Reporter:
                andreina J.Andreina
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                  Updated:
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