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7年前关闭。
在WordCount示例中,已知在map任务中接收单词并在reduce任务中总结那些“一个”。
我尝试添加System.out.println以显示wordcount示例代码如何在map / reduce任务中运行。当我在jobtracker的网页上读取stdout日志时,我注意到在map任务完成之前执行了一些“总结”工作,并在reduce任务中对map任务重做了“总结”。
即使它不会影响单词计数示例中的结果,也可能会影响其他工作。(做同样的工作两次!)
我已经修改了“mapred.reduce.slowstart.completed.maps”,但是它不起作用。
关于此问题有任何配置吗?