At Monitoring Console (MC) --> Search Activity : Instance, there is "top 20 Memory-consuming searches", which is searching from index=_introspection.
As I run the search, it is not recognizing saved search (scheduled search). Why doesn't the search starting index=_introspection recognize saved search (scheduled search)? It seems not it returns results from all searches.
How do I get to know memory consumption of all searches including saved search(scheduled search)? Do I have to join index=_introspection and index=_audit?
The DMC does indeed report on saved/scheduled searches. If you are not seeing them you might want to verify that all your instances are forwarding their _introspection logs and/or if they are properly configured for monitoring by the DMC.