On a cluster’s detail page, there is the Profiler tab. If you click on that, you are brought to the slow query profiler page. What’s not apparent from this view is that this page is not scoped to be cluster wide, but instead is scoped just to the primary mongo node. If you go back to the Overview tab, click on a specific shard on the left and then go to the profiler tab, you see how now, the title is shard specific and truly shows what you’re looking at? Please always display this shard name regardless of the breadcrumb to get there, e.g. if going from the cluster view, display the primary shard name.

I know this title thing seems small, but it caused me to open a support ticket because I didn’t see any of my slow queries show up as they were set to all run on secondary shards. I'm assuming this is probably true for other people.