Hi All, I have a single YARN application running on a cluster of 1 master node(Resourcemanager) and 3 slave nodes (Nodemanagers) - total memory= 24GB, total vcores= 12. I am using Hadoop 2.4.1 and scheduler is Capacity-Scheduler with DominantResourceCalculator. This application submits 10 container requests to ResourceManager through the asynchronous AMRM client ( AMRMClientAsync). The behavior I observed was that the container request asking for the most resources gets allocated first. For eg. 9 requests are for 2GB containers and 1 request is for a 4 GB container, then the 4GB container gets allocated and here's where it runs into a problem - It just stops there - it doesn't allocate any containers for all the 2 GB requests!
Once a container is allocated my app runs a task on it and once it is finished , app submits a fresh container request for this task (the tasks are of a repeating nature). Then again the RM allocates a 4GB container for this request, completely ignoring all the requests in between. I don't know if it is an issue with the AMRMClientAsync class- I haven't tried using the normal AMRMclient yet. Now I have tasks that require 2 GB and tasks that require 4 GB memory. Because of this problem it is only running the 4 GB task again and again. If all the container requests are identical in terms of resources, then this problem disappears and RM allocates all requested containers. Couldn't find any documentation/known bugs relating to this. I've hit a brick wall here, any help would be greatly appreciated. Thanks in advance -SMita
