Uploaded image for project: 'Hadoop Common'
  1. Hadoop Common
  2. HADOOP-6148

Implement a pure Java CRC32 calculator

    XMLWordPrintableJSON

Details

    • Improvement
    • Status: Closed
    • Major
    • Resolution: Fixed
    • None
    • 0.21.0
    • performance, util
    • None
    • Reviewed

    Description

      We've seen a reducer writing 200MB to HDFS with replication = 1 spending a long time in crc calculation. In particular, it was spending 5 seconds in crc calculation out of a total of 6 for the write. I suspect that it is the java-jni border that is causing us grief.

      Attachments

        1. hadoop-6148.txt
          25 kB
          Todd Lipcon
        2. hadoop-6148.txt
          25 kB
          Todd Lipcon
        3. hadoop-6148.txt
          25 kB
          Todd Lipcon
        4. TestCrc32Performance.java
          3 kB
          Scott Carey
        5. PureJavaCrc32NewLoop.java
          16 kB
          Scott Carey
        6. PureJavaCrc32NewInner.java
          16 kB
          Scott Carey
        7. PureJavaCrc32New.java
          16 kB
          Scott Carey
        8. benchmarks20090715.txt
          12 kB
          Tsz-wo Sze
        9. benchmarks20090714.txt
          9 kB
          Tsz-wo Sze
        10. PureJavaCrc32.java
          18 kB
          Tsz-wo Sze
        11. hdfs-297.txt
          19 kB
          Todd Lipcon
        12. TestCrc32Performance.java
          2 kB
          Scott Carey
        13. TestPureJavaCrc32.java
          3 kB
          Scott Carey
        14. PureJavaCrc32.java
          17 kB
          Scott Carey
        15. PureJavaCrc32.java
          2 kB
          Scott Carey
        16. PureJavaCrc32.java
          2 kB
          Scott Carey
        17. hadoop-5598.txt
          7 kB
          Todd Lipcon
        18. hadoop-5598-evil.txt
          8 kB
          Todd Lipcon
        19. TestCrc32Performance.java
          2 kB
          Todd Lipcon
        20. hadoop-5598-hybrid.txt
          11 kB
          Todd Lipcon
        21. crc32-results.txt
          3 kB
          Todd Lipcon
        22. TestCrc32Performance.java
          1 kB
          Todd Lipcon
        23. hadoop-5598.txt
          7 kB
          Todd Lipcon

        Issue Links

          Activity

            People

              scott_carey Scott Carey
              omalley Owen O'Malley
              Votes:
              0 Vote for this issue
              Watchers:
              20 Start watching this issue

              Dates

                Created:
                Updated:
                Resolved: