You can check for “yarn.app.mapreduce.am.resource.mb” in your configs. Its default is 1.5GB and other MR task defaults are 1GB.
From: darekg11 [mailto:[email protected]] Sent: Tuesday, November 17, 2015 11:34 AM To: [email protected] Subject: RE: Does MapReduceApplicationMaster prevents data node from spawning YarnChild? Thank You very much, will check but the problem is that machines aren't really powerful - only 2GB of RAM and 2xCore each at 3.3GHz. Do You maybe know approx value of required resources for AppMaster? And can we check current resource consumption of AppMaster? Dnia 17 listopada 2015 18:40 Bikas Saha <[email protected] <mailto:[email protected]> > napisał(a): No. In general App Masters and their containers can be launched on any machine and both can be launched on the same machine. If your case happens repeatedly then you could check the RM UI, while the job is running, to see the maximum resource on a node manager and the resource currently assigned. Perhaps your node managers don’t have enough resources to run multiple containers? From: darekg11 [mailto:[email protected]] Sent: Tuesday, November 17, 2015 7:55 AM To: [email protected] <mailto:[email protected]> Subject: Does MapReduceApplicationMaster prevents data node from spawning YarnChild? Hello again dear users. Today I ran into following problem: My mini cluster consist of: 1 NameNode and 2 SlaveNodes. When I ran my MapReduce program written in java with number of reducers equals to two. As the result on first SlaveNode I got MRAppMaster task and only the second slave launched Yarn Child which actually was producing output results. I understand that MRAppMaster is essential process repsonsible for managing life of given task. And because of that single slave node can't launch MrAppMaster and Yarn Child at the same time or am I misunderstanding something?
