Cloudera Manager provides various service metrics that can be graphed over time.
One useful metric for the Arcadia service is the resident memory for the analytics engine.
Within the chart builder, you can enter the following query:
select mem_rss where roleType=ARCENGINE
This will plot over time the resident memory usage for each arcengine daemon on each host. In the below example a stacked area chart quickly shows the total memory usage across four node cluster with a peak of ~20GB.