Hi , The mappers depend on source data only. But data definitely is going through all mappers, so I should get number of map jpbs as my output right? Instead I am getting only one.
Thanks and regards, Ravion On Fri, Aug 21, 2015 at 1:35 PM, ☼ R Nair (रविशंकर नायर) < [email protected]> wrote: > All, > > I have three mappers, followed by a reducer. I executed the map reduce > successfully. The reported output shows that number of mappers executed is > 1 and number of reducers is also 1. Though number of reducers are correct, > won't we be getting number of mappers as 3 , since I have three mapper > classes connected by ChainMapper? > > O/P given below (snippet) :- > > Job Counters > Launched map tasks=1 > Launched reduce tasks=1 > Data-local map tasks=1 > Total time spent by all maps in occupied slots (ms)=8853 > Total time spent by all reduces in occupied slots (ms)=9900 > Total time spent by all map tasks (ms)=8853 > Total time spent by all reduce tasks (ms)=9900 > Total vcore-seconds taken by all map tasks=8853 > Total vcore-seconds taken by all reduce tasks=9900 > Total megabyte-seconds taken by all map tasks=9065472 > Total megabyte-seconds taken by all reduce tasks=10137600 > > > What I guess is, since the output is passing through Context, the internal > connected mappers are not caught by job counter, am I correct ? > > Best, Ravion >
