Hi Deepak (DeepakGargMsft)
Have you checked out the "Insights" blade? If not, you can read more about ADX Insights in the doc and the post.
ADX Insights can help you assess the health of your cluster and detect the top CPU and memory consumers (users and applications), as well as other important aspects like the hot cache usage per table, batching ingestion monitoring, metalized views usage, and more.
ADX Insights is based on metrics and diagnostic logs that you should stream to a log analytics workspace. Once you enable the diagnostic logs, you can query the data using KQL. ADX Insights also surfaces Advisor recommendations.
The cluster memory is currently not exposed as a metric, but you can use Insights and the logs to monitor the memory consumption of your queries.
Let me know if there are any other questions. We can also set up a quick call to discuss these topics.