The MR1 teragen's mappers # depends on the total number of rows and demanded # of maps.
How are you passing -Dmapred.map.tasks=20 (no spaces) exactly? All generic options must go in before any other options do, so it should appear right after the word "teragen" in your command. On Wed, Dec 26, 2012 at 11:49 PM, anil gupta <[email protected]> wrote: > Hi All, > > I have 5 worker nodes and i have 4 map slots per node. So, i have 20 map > slots in my cluster. But when, i start my Teragen job, it only spawns 2 > mappers for entire job. I have even tried using the option > -Dmapred.map.tasks = 20 . Can anyone tell me how to force teragen to use 20 > mappers for generating the data? I am using cdh4.1.2 with Mapreducev1(Hadoop > 0.20.2) > -- > Thanks & Regards, > Anil Gupta -- Harsh J
