Excellent point sir On Monday, May 6, 2013, yypvsxf19870706 wrote:
> Hi > > Suppose that your input file are 10 with total size 64mb , I think you > will get the 10 maps. > > By the ways,the uber mode is only for yarn . Suppose you have actually > 1 map ,yarn will at least create two containers , one for app master and > the other for the map , if uber mode is enabled with the yarn , yarn will > only create 1 container for both app master and the map. > > > 发自我的 iPhone > > 在 2013-5-6，22:45，Rahul Bhattacharjee > <[email protected]<javascript:_e({}, 'cvml', > '[email protected]');>> > 写道： > > Hi, > > I was going through the definition of Uber Job of Hadoop. > > A job is considered uber when it has 10 or less maps , one reducer and the > complete data is less than one dfs block size. > > I have some doubts here- > > Splits are created as per the dfs block size.Creating 10 mappers are > possible from one block of data by some settings change (changing the max > split size). But trying to understand , why would some job need to run > around 10 maps for 64 MB of data. > One thing may be that the job is immensely CUP intensive. Will it be a > correct assumption? or is there is any other reason for this. > > Thanks, > Rahul > > > -- Sent from Gmail Mobile
