Intel® Advisor 2015 Help

Pane: Selected Site

Suitability Source window layout

Use this pane to view the predicted approximate performance for a selected site and its tasks.

Use This

To Do This

Link that displays either: Click here to display the scalability graph, or Click here to display annotation data

When the window height does not allow display of both the scalability graph with check boxes and the grid of annotation data, use these links to switch between displaying either the scalability graphic with site-specific check boxes or the grid of annotation data.

Scalability of Maximum Site Gain (scalability) graph

View a graph of the selected site's predicted maximum gain. The number of CPUs appears on the X axis and the program's run-time performance gain appears on the Y axis. Near the top of each vertical line a CPU number, you will see a box and a circle that indicate the minimum and maximum predicted gain values. If the minimum-maximum range appears in the:

  • Red-shaded area, this site is hurting your program's performance. Remove or significantly modify the site annotations.

  • Yellow-shaded area, this site is helping your program's performance, but maybe the gain may not be enough to justify the effort you needed to refactor and maintain your program. You should investigate how the results can be improved. Also, it might be more energy (power) efficient to increase the serial throughput using program changes or faster processors (parallel machines are designed to run at a lower clock frequency than certain serial machines).

  • Green-shaded area, this indicates good results. If you can achieve this level of performance, you will likely have a significant improvement to your program. The green area also indicates energy efficient (power) parallel speedups.

If the minimum-maximum range forms a flat line, this indicates that the maximum number of CPUs specified exceeds the number of task instances.

You can set the Target CPU Count in the All Sites pane interactively to update the graph and associated values in the Suitability Report. You can set the default value for the Target CPU Count in the Options > General dialog box. Use this dialog box to choose the Maximum CPU Count, which specifies the X axis values in the scalability graph and limits the maximum value allowed for the Target CPU Count in the Suitability Report window (see the help topic Dialog Box: Options - General under See Also below).

Overhead check boxes to the right of the scalability graph below Changes I will make to this site to improve performance.

Determine whether changing these items will impact the site's Maximum Site Gain value and its impact on the Maximum Program Gain for All Sites displayed in the All Sites pane:

These check boxes help you plan which parallel overhead or chunking items will be worthwhile when you add parallelism to your program. In the Recommended column, if Yes appears, the Intel Advisor analysis predicts it may be worthwhile for you to reduce the parallel overhead or enable chunking when you add parallel framework code to this site. If you agree to do this, select that check box. After you modify the modeling assumptions for the selected site, values are automatically calculated and updated.

Repeat this for each site in the All Sites pane.

Column labels

Click a column heading to sort in either ascending or descending order.

A link: Click here to display the scalability graph

A link: Click here to display annotation data

Toggle between displaying the suitability graph or the annotation data. These links only appear when the height is insufficient to display both the scalability graph and the annotation data.

Selected task data row

Review the predicted characteristics of each task in each column of the data grid. The columns are:

  • Annotation - annotation type, such as Task.

  • Annotation Label - label for that annotation

    Note

    If you see an Annotation Label of _too_deep_, this indicates that the call behavior of your program results in nesting of site and/or task annotations more deeply than Intel Advisor can handle. The deeper occurrences have all been merged into this _too_deep_ pseudo-site. This can indicate a problem with the placement of the annotation pair. For example, accidentally spanning scopes can result in unintentional nesting.

  • Source Location - the source file that contains the annotation and the line number. Icons indicate where source is available Code Location source code available icon or not available Code location source code not available icon.

  • Number of Instances - number of times the item occurs, such as the number of tasks created

  • Maximum Instance Time - maximum number of seconds to execute this task

  • Average Instance Time - average number of seconds to execute this task (approximate CPU time)

  • Minimum Instance Time - minimum number of seconds to execute this task (approximate CPU time)

  • Total Time - the number of seconds to execute this task (approximate CPU time)

Right click a data row to display a context menu

Display a context menu to: open the code editor to the corresponding source line, display the corresponding source line in the Suitability Source window, copy the selected data row(s) to the clipboard, or display context-sensitive help for that problem type.

See Also


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