title: hadoop map process error : percent descend to 0 , map completes became nagative number
body: <p>Strange that my job looks like this : </p>
  
  <p>The percent of map descends to 0.</p>
  
  <pre><code>13/02/15 06:04:44 INFO mapred.JobClient:  map 20% reduce 20%
  13/02/15 06:14:33 INFO mapred.JobClient:  map 19% reduce 20%
  13/02/15 06:22:30 INFO mapred.JobClient:  map 18% reduce 20%
  13/02/15 06:30:41 INFO mapred.JobClient:  map 17% reduce 20%
  13/02/15 06:40:39 INFO mapred.JobClient:  map 16% reduce 20%
  13/02/15 06:49:30 INFO mapred.JobClient:  map 15% reduce 20%
  13/02/15 06:57:41 INFO mapred.JobClient:  map 14% reduce 20%
  13/02/15 07:06:49 INFO mapred.JobClient:  map 13% reduce 20%
  13/02/15 07:16:22 INFO mapred.JobClient:  map 12% reduce 20%
  13/02/15 07:24:19 INFO mapred.JobClient:  map 11% reduce 20%
  13/02/15 07:33:22 INFO mapred.JobClient:  map 10% reduce 20%
  13/02/15 07:42:14 INFO mapred.JobClient:  map 9% reduce 20%
  13/02/15 07:50:47 INFO mapred.JobClient:  map 8% reduce 20%
  13/02/15 07:59:12 INFO mapred.JobClient:  map 7% reduce 20%
  13/02/15 08:08:04 INFO mapred.JobClient:  map 6% reduce 20%
  13/02/15 08:16:44 INFO mapred.JobClient:  map 5% reduce 20%
  13/02/15 08:25:26 INFO mapred.JobClient:  map 4% reduce 20%
  13/02/15 08:34:16 INFO mapred.JobClient:  map 3% reduce 20%
  13/02/15 08:42:21 INFO mapred.JobClient:  map 2% reduce 20%
  13/02/15 08:51:55 INFO mapred.JobClient:  map 1% reduce 20%
  13/02/15 08:59:56 INFO mapred.JobClient:  map 0% reduce 20%
  </code></pre>
  
  <p>And the Maps Completed is -4169</p>
  
  <pre><code>Jobid   Priority    User    Name    Map % Complete  Map Total   **Maps Completed**  Reduce % Complete   Reduce Total    Reduces Completed   Job Scheduling Information  Diagnostic Info
  job_201302111406_2339   NORMAL  hadoop  MonitorUVFreqStatMRPrepare  0.00%
  34140   **-4169**   20.92%
  60   0  NA  NA
  </code></pre>
  
  <p>Can anybody know what happens ?</p>