Function Aggregation
In most respects the Function Aggregation works exactly like the Process
Aggregation. It enables you to edit function group definitions and to choose a
function group for aggregation in a View. The only addition is that you can assign
colors to functions and function groups through the context menu\.
Open the Function Aggregation dialog box through
toolbar button.
Advanced > Function
Aggregation
or using the 
To see the full function name, hover your mouse over a group entry and see a
tooltip. The full function name (or static path) reflects the original definition of
the function or group as stored in the trace file.
You can also manage function groups through the context menu of the Function
Aggregation dialog box:

For example, to change the color of any of the functions, select the
Color
option from the context menu and apply a new color to the given function. To assign
the color of the parent node to all the children, use the
Assign Color to Children
entry of the context menu. This entry is enabled
only if a parent node is selected.