User Guide


Pane: GPU Roofline Chart

Use GPU Roofline chart to visualize actual performance of your GPU kernels against hardware-imposed performance ceilings. For more information about investigating GPU Roofline results, see Examine Bottlenecks on GPU Roofline Chart .
Families of Intel® X
graphics products starting with Intel® Arc™ Alchemist (formerly DG2) and newer generations feature GPU architecture terminology that shifts from legacy terms. For more information on the terminology changes and to understand their mapping with legacy content, see GPU Architecture Terminology for Intel® X

GPU Roofline Chart Controls

There are several controls to help you focus on the GPU Roofline chart data most important to you, including the following.
  • Select by Mouse Rect
    : Select one or more kernels by tracing a rectangle with your mouse.
  • Zoom by Mouse Rect
    : Zoom in and out by tracing a rectangle with your mouse. You can also zoom in and out using your mouse wheel.
  • Move View by Mouse
    : Move the chart left, right, up, and down.
  • Undo
    : Undo or redo the previous zoom action.
Use the filter drop-down to choose, which functions/loops to display on a Roofline chart. The following controls are available:
  • Use
    pane to filter kernels by type of operations: INT or FLOAT.
  • Use the
    Memory Level
    pane to show results for each kernel in the chart: CARM, L3, SLM, GTI.
Use the
drop-down to plot results from another Roofline chart on results of your current project.
Click the button to add results for comparison.
View and switch between the files that are currently compared in the
Compared Results
After comparison, the recent results are saved. You can view the list of recent results in the
Ready for Comparison
Add visual
to the GPU Roofline chart to make the interpretation of data easier, including performance limits and whether kernels are memory bound, compute bound, or both.
In the
drop-down toolbar, use the
Display roof rulers
checkbox to enable showing a vertical line from a kernel to the nearest and topmost performance ceilings. To view the ruler, hover the cursor over a kernel dot. Where the line intersects with each roof, labels display hardware performance limits for the kernel.
The preview picture is updated as you select guidance options, allowing you to see how changes will affect the GPU Roofline chart's appearance. Click
to apply your changes or
to return the GPU Roofline chart to its original appearance.
  • Roofline View Settings
    : Change the default scale setting to show:
    • The
      scale (default), which adjusts to a chosen GPU Roofline chart view.
    • A
      scale, which adjusts to the tallest or widest view and does not change when a different GPU Roofline chart view is chosen.
  • Roof Settings
    : Change the visibility and appearance of roofline representations (lines):
    • Click a
      checkbox to show/hide a roof line.
    • Click a
      checkbox to change a roof line appearance: display the roof line as a solid or a dashed line.
    • Manually fine-tune roof values in the
      column to set hardware limits specific to your code.
  • Loop Weight Representation
    : Change the appearance of dots:
    • Point Weight Calculation
      : Change the
      Base Value
      for a point weight calculation.
      For a GPU Roofline chart, only
      Self Elapsed Time
      is available as a base value.
    • Point Weight Ranges
      : Change the
      , and weight
      of a dot. Click the
      button to split a point weight range in two. Click the
      button to merge a point weight range with the range below.
    • Point Colorization
      : Color dots by
      weight ranges
      or by
      (vectorized or scalar). You can also change the color of loop with no self time.
  • Hover your mouse over a dot to display metrics and, if enabled, a roof ruler for it.
  • By default,
    Intel Advisor
    generates a roofline for
    GTI (Memory)
    , which reports memory traffic, in bytes, generated by all execution units.
    Double-click a dot or select a dot and press
    to display labeled dots representing memory levels for the selected kernel. Lines connect the dots to indicate that they correspond to the selected kernel.
    If you have chosen to display only
    memory levels in the chart using the
    Memory Level
    toolbar, unselected memory levels are displayed with
    To hide the labeled dots, do one of the following:
    • Select another kernel.
    • Double-click an empty space in the GPU Roofline chart.
    • Press
  • Click the
    button next to a dot on a chart to break it into smaller dots representing groups of instances of the same source kernel. Instances differ by global and local size.
    • Hover over each instance to view its performance metrics.
    • Select a dot representing an instance to highlight it in the
      pane and view detailed information about its performance and memory usage in the
      GPU Details
    • Double-click a dot representing an instance to view how it utilizes each memory level.
  • Right-click a kernel dot or a blank area in the Roofline chart to perform more functions, such as:
    • Further simplify the GPU Roofline chart by filtering out (temporarily hiding a dot), filtering in (temporarily hiding all other dots), and clearing filters (showing all originally displayed dots).
    • Show/hide a side panel that displays metrics for a selected dot.
    • Add visual guidance to the GPU Roofline chart to make the interpretation of data easier. These options are the same as in the

Product and Performance Information


Performance varies by use, configuration and other factors. Learn more at