Please try
2013/12/10 ch huang <[email protected]> > hi,maillist: > i try assign reduce number in commandline but seems not > useful,i run tera sort like this > > # hadoop jar /usr/lib/hadoop-mapreduce/hadoop-mapreduce-examples.jar > terasort /alex/terasort/1G-input /alex/terasort/1G-output > -Dmapreduce.job.reduces=34 > > so default mapred-site.xml assign reducer number is 16,i try run it with > 34 reducers,but the job run still as 16 reducers number,why? > > here is some output: > > Job Counters > Launched map tasks=1 > Launched reduce tasks=16 > Rack-local map tasks=1 > Total time spent by all maps in occupied slots (ms)=2318 > Total time spent by all reduces in occupied slots > (ms)=99714 >
