Span Markers
A span marker represents a meaningful phase of an application. For example, you can use a span to represent an interval of time during which a particular work item is being processed. Its length represents the duration of the corresponding application phase. This illustration shows a span in Concurrency Visualizer:
Sometimes span markers occur so close to one another in the Concurrency Visualizer that they can’t be drawn individually. When this occurs, a gray span aggregation marker that represents the underlying spans is shown. When you rest the pointer on one of these icons, a tooltip displays the number of underlying spans that are represented. To view the spans, zoom in. If you zoom in all the way and still get an span aggregation marker, you can view the underlying span markers in the Markers Report. This illustration shows a span aggregation marker:
