{"id":3599,"date":"2019-07-01T19:34:21","date_gmt":"2019-07-01T11:34:21","guid":{"rendered":"https:\/\/damogame.cn\/wordpress\/?p=3599"},"modified":"2019-07-01T19:34:21","modified_gmt":"2019-07-01T11:34:21","slug":"mapreduce","status":"publish","type":"post","link":"https:\/\/i007.cc\/wordpress\/archives\/3599","title":{"rendered":"MapReduce"},"content":{"rendered":"
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\u539f\u6587\u5730\u5740<\/a><\/div>\n
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2018.06.22 02:33*<\/span>\u00a0\u5b57\u6570 680<\/span>\u00a0\u9605\u8bfb 601<\/span>\u8bc4\u8bba 0<\/span>\u559c\u6b22 0<\/span><\/div>\n<\/div>\n<\/div>\n
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MapReduce\u662f\u4e00\u79cd\u7f16\u7a0b\u6a21\u578b\uff0c\u7528\u4e8e\u5927\u89c4\u6a21\u6570\u636e\u96c6\u7684\u5e76\u884c\u8fd0\u7b97<\/p>\n

\u5728\u8fdb\u884cMapReduce\u8ba1\u7b97\u4efb\u52a1\u7684\u65f6\u5019\uff0c\u4efb\u52a1\u88ab\u5206\u4e3a\u4e24\u4e2a\u9636\u6bb5\uff1aMap\u9636\u6bb5\u548cReduce\u9636\u6bb5\u3002\u6bcf\u4e2a\u9636\u6bb5\u90fd\u662f\u7528\u952e\u503c\u5bf9(key\/value)\u5f62\u5f0f\u4f5c\u4e3a\u8f93\u5165(input)\u548c\u8f93\u51fa(output)<\/p>\n

MapReduce\u91c7\u7528\u7684\u662f\u201c\u5206\u800c\u6cbb\u4e4b\u201d\u7684\u7b56\u7565\uff0c\u4e00\u4e2a\u5927\u89c4\u6a21\u6570\u636e\u96c6\u4f1a\u88ab\u5207\u5206\u6210\u8bb8\u591a\u72ec\u7acb\u7684\u5206\u7247\uff0c\u8fd9\u4e9b\u5206\u7247\u53ef\u4ee5\u88ab\u591a\u4e2aMap\u4efb\u52a1\u5e76\u884c\u5904\u7406<\/p>\n

MapReduce\u6846\u67b6\u91c7\u7528Master\/Slave\u67b6\u6784\uff0c\u5305\u62ec\u4e00\u4e2aMaster\u548c\u591a\u4e2aSlave\u3002Master\u4e0a\u9762\u8fd0\u884cJobTracker\uff0cSlave\u4e0a\u9762\u8fd0\u884cTaskTracker\u3002<\/p>\n

MapReduce\u4e3b\u8981\u75314\u4e2a\u90e8\u5206\u7ec4\u6210\uff1a<\/p>\n

    \n
  1. Client
    \n\u7528\u6237\u7f16\u5199\u7684MapReduce\u7a0b\u5e8f\u901a\u8fc7Client\u63d0\u4ea4\u5230JobTracker\u7aef
    \n\u7528\u6237\u53ef\u901a\u8fc7Client\u63d0\u4f9b\u7684\u4e00\u4e9b\u63a5\u53e3\u67e5\u770b\u4f5c\u4e1a\u8fd0\u884c\u72b6\u6001<\/li>\n
  2. JobTracker
    \nJobTracker\u8d1f\u8d23\u8d44\u6e90\u76d1\u63a7\u548c\u4f5c\u4e1a\u8c03\u5ea6
    \nJobTracker \u76d1\u63a7\u6240\u6709TaskTracker\u4e0eJob\u7684\u5065\u5eb7\u72b6\u51b5\uff0c\u4e00\u65e6\u53d1\u73b0\u5931\u8d25\uff0c\u5c31\u5c06\u76f8\u5e94\u7684\u4efb\u52a1\u8f6c\u79fb\u5230\u5176\u4ed6\u8282\u70b9
    \nJobTracker \u4f1a\u8ddf\u8e2a\u4efb\u52a1\u7684\u6267\u884c\u8fdb\u5ea6\u3001\u8d44\u6e90\u4f7f\u7528\u91cf\u7b49\u4fe1\u606f\uff0c\u5e76\u5c06\u8fd9\u4e9b\u4fe1\u606f\u544a\u8bc9\u4efb\u52a1\u8c03\u5ea6\u5668\uff0c\u800c\u8c03\u5ea6\u5668\u4f1a\u5728\u8d44\u6e90\u51fa\u73b0\u7a7a\u95f2\u65f6\uff0c\u9009\u62e9\u5408\u9002\u7684\u4efb\u52a1\u53bb\u4f7f\u7528\u8fd9\u4e9b\u8d44\u6e90<\/li>\n
  3. TaskTracker
    \nTaskTracker \u4f1a\u5468\u671f\u6027\u5730\u901a\u8fc7\u201c\u5fc3\u8df3\u201d\u5c06\u672c\u8282\u70b9\u4e0a\u8d44\u6e90\u7684\u4f7f\u7528\u60c5\u51b5\u548c\u4efb\u52a1\u7684\u8fd0\u884c\u8fdb\u5ea6\u6c47\u62a5\u7ed9JobTracker\uff0c\u540c\u65f6\u63a5\u6536JobTracker \u53d1\u9001\u8fc7\u6765\u7684\u547d\u4ee4\u5e76\u6267\u884c\u76f8\u5e94\u7684\u64cd\u4f5c
    \nTaskTracker \u4f7f\u7528\u201cslot\u201d\u7b49\u91cf\u5212\u5206\u672c\u8282\u70b9\u4e0a\u7684\u8d44\u6e90\u91cf\uff08CPU\u3001\u5185\u5b58\u7b49\uff09\u3002\u4e00\u4e2aTask \u83b7\u53d6\u5230\u4e00\u4e2aslot \u540e\u624d\u6709\u673a\u4f1a\u8fd0\u884c\uff0c\u800cHadoop\u8c03\u5ea6\u5668\u7684\u4f5c\u7528\u5c31\u662f\u5c06\u5404\u4e2aTaskTracker\u4e0a\u7684\u7a7a\u95f2slot\u5206\u914d\u7ed9Task\u4f7f\u7528\u3002slot \u5206\u4e3aMap slot \u548cReduce slot \u4e24\u79cd\uff0c\u5206\u522b\u4f9bMapTask \u548cReduce Task \u4f7f\u7528<\/li>\n
  4. HDFS
    \n\u4fdd\u5b58\u4f5c\u4e1a\u7684\u6570\u636e\u3001\u914d\u7f6e\u4fe1\u606f\u7b49\u7b49\uff0c\u6700\u540e\u7684\u7ed3\u679c\u4e5f\u662f\u4fdd\u5b58\u5728HDFS\u4e0a\u9762<\/li>\n<\/ol>\n

    MapReduce\u57fa\u672c\u67b6\u6784\uff1a<\/p>\n

    \n
    \n
    <\/div>\n
    <\/div>\n<\/div>\n
    4162886-22e98e6334639711.png<\/div>\n<\/div>\n

    MapReduce\u8fd0\u884c\u8fc7\u7a0b\uff1a<\/p>\n

    \n
    \n
    <\/div>\n
    <\/div>\n<\/div>\n
    5959612-68cf8d92e2358294.png<\/div>\n<\/div>\n

    MapReduce\u7684\u8ba1\u7b97\u6d41\u7a0b\uff1a
    \nInput Split –> Map –> Combiner(optional) –> Shuffle –> Reduce –> Output<\/p>\n

    \n
    \n
    <\/div>\n
    <\/div>\n<\/div>\n
    20160419199999.jpg<\/div>\n<\/div>\n

    Combine\uff1a\u4f5c\u7528\u662f\u628a\u540c\u4e00\u4e2akey\u7684\u952e\u503c\u5bf9\u5408\u5e76\u5728\u4e00\u8d77\uff0ccombine\u51fd\u6570\u628a\u4e00\u4e2amap\u51fd\u6570\u4ea7\u751f<key,value>\u5bf9\u5408\u5e76\u6210\u4e00\u4e2a\u65b0\u7684<key,value>\u5bf9\uff0c\u5e76\u5c06\u65b0\u7684<key,value>\u4f5c\u4e3a\u8f93\u5165\u5230reduce\u51fd\u6570\u4e2d<\/p>\n

    Partition\uff1a\u4f5c\u7528\u5c31\u662f\u628a\u8fd9\u4e9b\u6570\u636e\u5f52\u7c7b\uff0c\u4e3b\u8981\u5728Shuffle\u8fc7\u7a0b\u4e2d\u6309\u7167Key\u503c\u5c06\u4e2d\u95f4\u7ed3\u679c\u5206\u6210R\u4efd\uff0c\u5176\u4e2d\u6bcf\u4efd\u90fd\u6709\u4e00\u4e2aReduce\u53bb\u8d1f\u8d23\uff0c\u53ef\u4ee5\u901a\u8fc7job.setPartitionerClass()\u65b9\u6cd5\u8fdb\u884c\u8bbe\u7f6e\uff0c\u9ed8\u8ba4\u7684\u4f7f\u7528hashPartitioner\u7c7b<\/p>\n

    Shuffle\uff1ashuffle\u662fmap\u548creduce\u4e2d\u95f4\u7684\u8fc7\u7a0b\uff0c\u5305\u542b\u4e24\u7aef\u7684Combine\u548cPartition<\/p>\n<\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"

    \u539f\u6587\u5730\u5740 2018.06.22 02:3<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"colormag_page_container_layout":"default_layout","colormag_page_sidebar_layout":"default_layout","footnotes":""},"categories":[],"tags":[119],"class_list":["post-3599","post","type-post","status-publish","format-standard","hentry","tag-03-"],"_links":{"self":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/posts\/3599","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/comments?post=3599"}],"version-history":[{"count":0,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/posts\/3599\/revisions"}],"wp:attachment":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/media?parent=3599"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/categories?post=3599"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/tags?post=3599"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}