What all goes behind the scene, when a mongoDB chart / dashboard is run?

I have many standard DB views (with their aggregate pipeline), created on source collections, and mongoDB charts built on top of them. I use “Explain” feature to get the performance of the view (which is fairly fast mostly), however the charts which are built on top of those views take a long time. I know the chart itself has it’s own aggregate pipeline (and filters) which might be in play. But, how can I check how much time the charting pipeline is taking Vs the datasource. Unless one have a way to know that, its difficult for anyone to work out any possible perf improvements.