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  1. HBase
  2. HBASE-6852

SchemaMetrics.updateOnCacheHit costs too much while full scanning a table with all of its fields

    Details

    • Type: Improvement
    • Status: Closed
    • Priority: Minor
    • Resolution: Fixed
    • Affects Version/s: 0.94.0
    • Fix Version/s: 0.94.3
    • Component/s: metrics
    • Labels:
    • Hadoop Flags:
      Reviewed

      Description

      The SchemaMetrics.updateOnCacheHit costs too much while I am doing the full table scanning.
      Here is the top 5 hotspots within regionserver while full scanning a table: (Sorry for the less-well-format)

      CPU: Intel Westmere microarchitecture, speed 2.262e+06 MHz (estimated)
      Counted CPU_CLK_UNHALTED events (Clock cycles when not halted) with a unit mask of 0x00 (No unit mask) count 5000000
      samples % image name symbol name
      -------------------------------------------------------------------------------
      98447 13.4324 14033.jo void org.apache.hadoop.hbase.regionserver.metrics.SchemaMetrics.updateOnCacheHit(org.apache.hadoop.hbase.io.hfile.BlockType$BlockCategory, boolean)
      98447 100.000 14033.jo void org.apache.hadoop.hbase.regionserver.metrics.SchemaMetrics.updateOnCacheHit(org.apache.hadoop.hbase.io.hfile.BlockType$BlockCategory, boolean) [self]
      -------------------------------------------------------------------------------
      45814 6.2510 14033.jo int org.apache.hadoop.hbase.KeyValue$KeyComparator.compareRows(byte[], int, int, byte[], int, int)
      45814 100.000 14033.jo int org.apache.hadoop.hbase.KeyValue$KeyComparator.compareRows(byte[], int, int, byte[], int, int) [self]
      -------------------------------------------------------------------------------
      43523 5.9384 14033.jo boolean org.apache.hadoop.hbase.regionserver.StoreFileScanner.reseek(org.apache.hadoop.hbase.KeyValue)
      43523 100.000 14033.jo boolean org.apache.hadoop.hbase.regionserver.StoreFileScanner.reseek(org.apache.hadoop.hbase.KeyValue) [self]
      -------------------------------------------------------------------------------
      42548 5.8054 14033.jo int org.apache.hadoop.hbase.KeyValue$KeyComparator.compare(byte[], int, int, byte[], int, int)
      42548 100.000 14033.jo int org.apache.hadoop.hbase.KeyValue$KeyComparator.compare(byte[], int, int, byte[], int, int) [self]
      -------------------------------------------------------------------------------
      40572 5.5358 14033.jo int org.apache.hadoop.hbase.io.hfile.HFileBlockIndex$BlockIndexReader.binarySearchNonRootIndex(byte[], int, int, java.nio.ByteBuffer, org.apache.hadoop.io.RawComparator)~1
      40572 100.000 14033.jo int org.apache.hadoop.hbase.io.hfile.HFileBlockIndex$BlockIndexReader.binarySearchNonRootIndex(byte[], int, int, java.nio.ByteBuffer, org.apache.hadoop.io.RawComparator)~1 [self]

        Attachments

        1. 6852-0.94_3.patch
          7 kB
          Cheng Hao
        2. 6852-0.94_2.patch
          8 kB
          Cheng Hao
        3. 6852-0.94.txt
          7 kB
          Lars Hofhansl
        4. metrics_hotspots.png
          57 kB
          Cheng Hao
        5. onhitcache-trunk.patch
          7 kB
          Cheng Hao

          Activity

            People

            • Assignee:
              hcheng Cheng Hao
              Reporter:
              hcheng Cheng Hao
            • Votes:
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              Dates

              • Created:
                Updated:
                Resolved: