CPU Call Stack and GPU Stream

one of two GPU Time Line reporting areas

The GPU Time Line report is divided into two general areas. The upper half of the window shows CPU Stack and GPU Stream data over time, and contains the related controls.

Stack

The Stack display shows the call stack levels of the program running on the CPU, starting with 0 (main) at the top. Use the scroll bar controls at the right end of the display to move through the call stack levels. If the window is resized so that all levels are visible, the scroll bar controls are inactive.

Each box in the Stack display represents an interval of execution, typically an instance of a function call. Vertically stacked boxes represent functions calling other functions. Green boxes are transfers between the CPU and GPU, red boxes are wait-related functions, and all others are blue. Hovering the cursor over a box to see a popup that describes the event and any related GPU events also change color to highlight the relationship. Alternatively, left-clicking while hovering will turn the popup into a separate window.

Stream

The Stream displays shows the related GPU activity during the same period in time. Each box represents GPU stream activity, and the user can use the scroll bar controls at the right end of the Stream display to move through the stream activity levels. The color-coding and hover/popup behavior are the same as for the Stack section.

You can use the windowshade control between the Stack and Stream displays to change the relative sizes of the displays.

time line

The horizontal scroll bar immediately below the Stream display shows the time interval represented by the Stack and Stream displays. The red vertical bar is the center-point of the current display, and also the value shown in the Time entry field. You can left-click anywhere on the scroll bar to re-center the display on another point in time. The scale of this scroll bar is determined by the Magnify control.

Magnify

The Magnify control determines the scale of the horizontal time line that in turn defines the region shown in the Stack and Stream displays. At a setting of 1.0, the time line duration is the same as the entire duration of the program. Use higher magnification levels to reveal finer granularity in the data.

Time

Entering a value in the Time entry field will jump directly to that point in time during program execution and re-center the display on that point in time.

Func

The Func entry field enables the user to search for instances of a specific function by name. As the function name is entered, a drop-down list appears, showing all matching names within the program. After entering or selecting a function, use the Prev and Next buttons to move to the previous or next instance of the function.