Pane: Call Stack
- User-mode sampling and tracing collection, such as Hotspots and Threading analyses
Stack metric drop-down menu. Select a performance metric to explore the distribution of this metric over stacks of the selected object. For example, for the Threading Efficiency viewpoint the Wait Time metric is preselected. For the GPU Offload viewpoint, the Execution metric is preselected.
Navigation bar. Click the next/previous arrows to view stacks for the selected program unit(s). The stack types are classified by metrics and depend on the selected viewpoint. For example, for the
Threading Efficiencyviewpoint the
Wait Timestack type displays call stacks where the object selected in the grid contributed to the application Wait time.
When multiple stacks lead to the selected program unit, the
Call Stackpane shows the stack that contributed most to the metric value, the
hottest path, as the first stack. To see other stacks, click the navigation arrows.
Contribution bar. Analyze the indicator of the contribution of the currently visible stack to the overall metric data for the selected program unit(s). If you select a single stack in the result window, the Contribution bar shows 100%. If more than one program unit is selected, all the related stacks are added to the calculation.
In the example above, the function selected in the
Bottom-upgrid had 3 Wait Time stacks leading to it with the total Wait time 23.718 seconds. The first stack is responsible for 97.9% (or 23.230s) of the overall 23.718 seconds. Note that the Bottom-up grid aggregates all 3 stacks into one since all of them go to the same function in different code lines.
Call stack for a program unit selected in the grid or in the Timeline pane. Analyze the call sequence for the selected function according to the stack metric selected in the navigation bar. Each row in the stack represents a function (with an RVA and a line number of the call site, if available) that called the function in the row above it. When the
Call Stack Modeon the filter toolbar is set to
Only user functions, the system functions are shown at the bottom of the stack. When set to
User/system functions, the system functions are shown in the correct location, according to the call sequence.
Click a hyperlink or double-click a function in the stack to open the source exactly where this function was called.
If you see
[Unknown frame(s)]identifiers in the stack, it means that the
VTunecould not locate symbol files for system or your application modules. See the Resolving Unknown Frames topic for more details.
Context menu.Manage the call stack representation in the
Call Stackpane (applicable to all stacks). Right-click and select an option. For example, you may de-select the
Show in One-Line Modeoption to view functions in two lines: