Question about how to find which file takes the longest time to process and how to assign more mappers to process that particular file

Hello, I have a question about how to find which file takes the longest time to process and how to assign more mappers to process that particular file. Currently, about three mapper takes about five times more time to complete. So, how can I detect which specific files are those three mapper

Re: Question about how to find which file takes the longest time to process and how to assign more mappers to process that particular file

Hi, Roughly, this information will be available under the 'Hadoop map task list' page in the Mapreduce web ui (in Hadoop-1.0, which I am assuming is what you are using). You can reach this page by selecting the running tasks link from the job information page. The page has a table that lists all