Reachability scopes distribute objects according to how/whether they are reachable from GC roots.
This information is helpful when analysing the profiled application's memory consumption and searching for memory leaks. Also it helps examining excessive garbage allocation, especially if the snapshot doesn't contain recorded object allocation information.
Object.finalize()will be placed to the finalizer queue before actual deletion.
In addition to the "Reachability scopes" view, objects view header shows brief summary on the number of strong reachable objects, and if there are any, provides an easy way to open them in new tab, by clicking corresponding link (useful when analysing memory leaks):
Action Memory | Instances by Class... (Ctrl+N) allows you to choose the reachability scope of objects to open:
The reachability scope for individual objects is shown in reference explorers and paths views: