How mapred.map.child.java.opts influence the Container resource allocation

[YouPeng Yang]

Hi All

    I use YARN and MR.I am confused by the relationship between
mapred.map.child.java.opts and  Container resource  allocation.
    if I setup mapred.map.child.java.opts = -Xmx2048m ,on nodemanager
how Containers will be allocated according to this settings.
     what about mapred.reduce.child.java.opts?

regards
Youpeng Yang