Adjust Ambari server heap size

Adjust the heap size on the Ambari server host to increase available memory.

1. On the Ambari server host, edit the ambari-env.sh file:
   vi /var/lib/ambari-server/ambari-env.sh
2. For the AMBARI_JVM_ARGS variable, replace the default -Xmx2048m with a value such as: -Xmx4GB -Xmn2GB based on the number of nodes in your cluster. Use the following recommendations as guidance:

   Table 1. Recommended Ambari Server heap size settings for large clusters

   Number of Cluster Nodes	Xmx value	Xmn value
   100 - 400	4 GB	2 GB
   400 - 800	4 GB	2 GB
   800 - 1200	8 GB	2 GB
   1200 - 1600	16 GB	2.4 GB