Control the overview

Right-click on the Overview pane to change the view options.

This menu includes:

By Timestamp
Show the events sorted by their timestamp. Because several memory events can occur with the same time stamp, this might present the events in a confusing order (for example, a buffer's allocation and deallocation events could be shown in the wrong order if they happen during the sampling interval).
By Count
Show events sorted by their event index. This is the default ordering in the Overview pane.
Filter the events that are shown by size, type, or both. You can also hide the matching allocations and deallocations, so that you see only the unmatched ones:

Zoom In
Zoom in on the selected range of events.
Zoom Out
Zoom out to the set of memory events that you previously zoomed in on.