Details

    • Type: Improvement
    • Status: Resolved
    • Priority: Major
    • Resolution: Fixed
    • Affects Version/s: None
    • Fix Version/s: 3.0.0-alpha1
    • Component/s: task
    • Labels:
      None
    • Environment:

      x86-64 Linux/Unix

    • Hadoop Flags:
      Reviewed
    • Release Note:
      Hide
      Adds a native implementation of the map output collector. The native library will build automatically with -Pnative. Users may choose the new collector on a job-by-job basis by setting mapreduce.job.map.output.collector.class=org.apache.hadoop.mapred.
      nativetask.NativeMapOutputCollectorDelegator in their job configuration. For shuffle-intensive jobs this may provide speed-ups of 30% or more.
      Show
      Adds a native implementation of the map output collector. The native library will build automatically with -Pnative. Users may choose the new collector on a job-by-job basis by setting mapreduce.job.map.output.collector.class=org.apache.hadoop.mapred. nativetask.NativeMapOutputCollectorDelegator in their job configuration. For shuffle-intensive jobs this may provide speed-ups of 30% or more.
    • Tags:
      optimization task

      Description

      I'm recently working on native optimization for MapTask based on JNI.

      The basic idea is that, add a NativeMapOutputCollector to handle k/v pairs emitted by mapper, therefore sort, spill, IFile serialization can all be done in native code, preliminary test(on Xeon E5410, jdk6u24) showed promising results:

      1. Sort is about 3x-10x as fast as java(only binary string compare is supported)

      2. IFile serialization speed is about 3x of java, about 500MB/s, if hardware CRC32C is used, things can get much faster(1G/

      3. Merge code is not completed yet, so the test use enough io.sort.mb to prevent mid-spill

      This leads to a total speed up of 2x~3x for the whole MapTask, if IdentityMapper(mapper does nothing) is used

      There are limitations of course, currently only Text and BytesWritable is supported, and I have not think through many things right now, such as how to support map side combine. I had some discussion with somebody familiar with hive, it seems that these limitations won't be much problem for Hive to benefit from those optimizations, at least. Advices or discussions about improving compatibility are most welcome

      Currently NativeMapOutputCollector has a static method called canEnable(), which checks if key/value type, comparator type, combiner are all compatible, then MapTask can choose to enable NativeMapOutputCollector.

      This is only a preliminary test, more work need to be done. I expect better final results, and I believe similar optimization can be adopt to reduce task and shuffle too.

        Attachments

        1. MAPREDUCE-2841.v1.patch
          180 kB
          Binglin Chang
        2. dualpivot-0.patch
          5 kB
          Chris Douglas
        3. dualpivotv20-0.patch
          4 kB
          Chris Douglas
        4. MAPREDUCE-2841.v2.patch
          190 kB
          Binglin Chang
        5. DESIGN.html
          42 kB
          Binglin Chang
        6. fb-shuffle.patch
          76 kB
          Todd Lipcon
        7. hadoop-3.0-mapreduce-2841-2014-7-17.patch
          3.50 MB
          Sean Zhong
        8. micro-benchmark.txt
          13 kB
          Todd Lipcon
        9. MR-2841benchmarks.pdf
          213 kB
          Todd Lipcon
        10. mr-2841-merge.txt
          2.72 MB
          Todd Lipcon
        11. mr-2841-merge-2.txt
          2.70 MB
          Sean Zhong
        12. mr-2841-merge-3.patch
          2.73 MB
          Sean Zhong
        13. mr-2841-merge-4.patch
          2.68 MB
          Sean Zhong

          Issue Links

          1.
          Allow specifying multiple MapOutputCollectors with fallback Sub-task Closed Todd Lipcon
          2.
          Fix native-task build on Ubuntu 13.10 Sub-task Resolved Todd Lipcon
          3.
          native-task should not fail to build if snappy is missing Sub-task Resolved Sean Zhong
          4.
          Fix or suppress native-task gcc warnings Sub-task Resolved Manu Zhang
          5.
          native-task CompressTest failure on Ubuntu Sub-task Resolved Manu Zhang
          6.
          native-task: reuse lz4 sources in hadoop-common Sub-task Resolved Binglin Chang
          7.
          native-task: Fix build on macosx Sub-task Resolved Binglin Chang
          8.
          native-task: Unit test TestGlibCBug fails on ubuntu Sub-task Resolved Sean Zhong
          9.
          native-task should not run unit tests if native profile is not enabled Sub-task Resolved Binglin Chang
          10.
          native-task test logs should not write to console Sub-task Open Unassigned
          11.
          native-task: simplify/remove dead code Sub-task Resolved Unassigned
          12.
          native-task: TestBytesUtil fails Sub-task Resolved Todd Lipcon
          13.
          native-task: revert changes which expose Text internals Sub-task Resolved Todd Lipcon
          14.
          native-task: Rename system tests into standard directory layout Sub-task Resolved Todd Lipcon
          15.
          native-task: Use DirectBufferPool from Hadoop Common Sub-task Resolved Todd Lipcon
          16.
          native-task: Simplify ByteBufferDataReader/Writer Sub-task Resolved Todd Lipcon
          17.
          native-task should not fail to build if zlib is missing Sub-task Resolved Unassigned
          18.
          native-task: fix some valgrind errors Sub-task Resolved Binglin Chang
          19.
          native-task: add native tests to maven and fix bug in pom.xml Sub-task Resolved Binglin Chang
          20.
          native-task: fix native library distribution Sub-task Resolved Manu Zhang
          21.
          native-task: fix logging Sub-task Resolved Manu Zhang
          22.
          native-task: sources/test-sources jar distribution Sub-task Resolved Manu Zhang
          23.
          native-task: speed up test runs Sub-task Resolved Todd Lipcon
          24.
          native-task: findbugs, interface annotations, and other misc cleanup Sub-task Resolved Todd Lipcon
          25.
          nativetask: move system test working dir to target dir and cleanup test config xml files Sub-task Resolved Manu Zhang
          26.
          native-task: KVTest and LargeKVTest should check mr job is sucessful Sub-task Resolved Binglin Chang
          27.
          native-task: warnings about illegal Progress values Sub-task Resolved Manu Zhang
          28.
          native-task: fix some counter issues Sub-task Resolved Binglin Chang
          29.
          native-task: Style fixups and dead code removal Sub-task Resolved Todd Lipcon
          30.
          native-task: fix release audit, javadoc, javac warnings Sub-task Resolved Todd Lipcon
          31.
          Remove CustomModule examples in nativetask Sub-task Resolved Sean Zhong
          32.
          native-task: fix gtest build on macosx Sub-task Resolved Binglin Chang

            Activity

              People

              • Assignee:
                clockfly Sean Zhong
                Reporter:
                decster Binglin Chang
              • Votes:
                4 Vote for this issue
                Watchers:
                83 Start watching this issue

                Dates

                • Created:
                  Updated:
                  Resolved: