爲什麼減少停留在16％？

我有一個減少地圖的工作我試圖在一個相對較小的數據集上運行。我一直遇到一個問題，減少的工作一直停留在16％。我的任務跟蹤日誌閱讀：爲什麼減少停留在16％？

2012-03-21 17:09:23,829 INFO org.apache.hadoop.mapred.TaskTracker: attempt_201203211704_0001_r_000000_0 0.16666667% reduce > copy (1 of 2 at 0.16 MB/s) 
2012-03-21 17:09:26,865 INFO org.apache.hadoop.mapred.TaskTracker: attempt_201203211704_0001_r_000000_0 0.16666667% reduce > copy (1 of 2 at 0.16 MB/s) 
2012-03-21 17:09:32,902 INFO org.apache.hadoop.mapred.TaskTracker: attempt_201203211704_0001_r_000000_0 0.16666667% reduce > copy (1 of 2 at 0.16 MB/s) 
2012-03-21 17:09:38,938 INFO org.apache.hadoop.mapred.TaskTracker: attempt_201203211704_0001_r_000000_0 0.16666667% reduce > copy (1 of 2 at 0.16 MB/s) 
2012-03-21 17:09:41,973 INFO org.apache.hadoop.mapred.TaskTracker: attempt_201203211704_0001_r_000000_0 0.16666667% reduce > copy (1 of 2 at 0.16 MB/s) 
2012-03-21 17:09:48,010 INFO org.apache.hadoop.mapred.TaskTracker: attempt_201203211704_0001_r_000000_0 0.16666667% reduce > copy (1 of 2 at 0.16 MB/s) 
2012-03-21 17:09:51,045 INFO org.apache.hadoop.mapred.TaskTracker: attempt_201203211704_0001_r_000000_0 0.16666667% reduce > copy (1 of 2 at 0.16 MB/s) 
2012-03-21 17:09:57,086 INFO org.apache.hadoop.mapred.TaskTracker: attempt_201203211704_0001_r_000000_0 0.16666667% reduce > copy (1 of 2 at 0.16 MB/s) 
2012-03-21 17:10:03,120 INFO org.apache.hadoop.mapred.TaskTracker: attempt_201203211704_0001_r_000000_0 0.16666667% reduce > copy (1 of 2 at 0.16 MB/s) 
2012-03-21 17:10:06,154 INFO org.apache.hadoop.mapred.TaskTracker: attempt_201203211704_0001_r_000000_0 0.16666667% reduce > copy (1 of 2 at 0.16 MB/s) 
2012-03-21 17:10:12,198 INFO org.apache.hadoop.mapred.TaskTracker: attempt_201203211704_0001_r_000000_0 0.16666667% reduce > copy (1 of 2 at 0.16 MB/s) 
2012-03-21 17:10:18,234 INFO org.apache.hadoop.mapred.TaskTracker: attempt_201203211704_0001_r_000000_0 0.16666667% reduce > copy (1 of 2 at 0.16 MB/s) 
2012-03-21 17:10:21,271 INFO org.apache.hadoop.mapred.TaskTracker:> attempt_201203211704_0001_r_000000_0 0.16666667% reduce > copy (1 of 2 at 0.16 MB/s) 
2012-03-21 17:10:27,310 INFO org.apache.hadoop.mapred.TaskTracker: attempt_201203211704_0001_r_000000_0 0.16666667% reduce > copy (1 of 2 at 0.16 MB/s) 
2012-03-21 17:10:33,342 INFO org.apache.hadoop.mapred.TaskTracker: attempt_201203211704_0001_r_000000_0 0.16666667% reduce > copy (1 of 2 at 0.16 MB/s) 
2012-03-21 17:10:36,374 INFO org.apache.hadoop.mapred.TaskTracker: attempt_201203211704_0001_r_000000_0 0.16666667% reduce > copy (1 of 2 at 0.16 MB/s) 
2012-03-21 17:10:42,403 INFO org.apache.hadoop.mapred.TaskTracker: attempt_201203211704_0001_r_000000_0 0.16666667% reduce > copy (1 of 2 at 0.16 MB/s) 
2012-03-21 17:10:48,435 INFO org.apache.hadoop.mapred.TaskTracker: attempt_201203211704_0001_r_000000_0 0.16666667% reduce > copy (1 of 2 at 0.16 MB/s) 
2012-03-21 17:10:51,462 INFO org.apache.hadoop.mapred.TaskTracker: attempt_201203211704_0001_r_000000_0 0.16666667% reduce > copy (1 of 2 at 0.16 MB/s) 
2012-03-21 17:10:57,495 INFO org.apache.hadoop.mapred.TaskTracker: attempt_201203211704_0001_r_000000_0 0.16666667% reduce > copy (1 of 2 at 0.16 MB/s) 
2012-03-21 17:11:03,523 INFO org.apache.hadoop.mapred.TaskTracker: attempt_201203211704_0001_r_000000_0 0.16666667% reduce > copy (1 of 2 at 0.16 MB/s) 
2012-03-21 17:11:06,545 INFO org.apache.hadoop.mapred.TaskTracker: attempt_201203211704_0001_r_000000_0 0.16666667% reduce > copy (1 of 2 at 0.16 MB/s) 
2012-03-21 17:11:12,578 INFO org.apache.hadoop.mapred.TaskTracker: attempt_201203211704_0001_r_000000_0 0.16666667% reduce > copy (1 of 2 at 0.16 MB/s) 
2012-03-21 17:11:18,607 INFO org.apache.hadoop.mapred.TaskTracker: attempt_201203211704_0001_r_000000_0 0.16666667% reduce > copy (1 of 2 at 0.16 MB/s)

來源

2012-03-21 rsman

它看起來好像在慢慢複製數據 – 2012-03-21 21:28:36

我打開一個文件系統對象，並沒有在文件被accesssed映射器關閉它。在map（）定義的末尾添加fs.close（）可以解決問題。

來源

2012-03-22 02:42:04 rsman

感謝您發佈問題的答案，您幫我追蹤了一個真正的問題！ – 2012-12-13 06:42:56

爲什麼減少停留在16％？

回答

相關問題