Compare with Previous Result

You optimized your code to apply a loop interchange mechanism that gave you 19.633 seconds of improvement in the application execution time. To understand whether you got rid of the hotspot and what kind of optimization you got per function, re-run the Basic Hotspots analysis on the optimized code and compare results:

  1. Compare results before and after optimization.

  2. Identify the performance gain.

Compare Results Before and After Optimization

  1. Run the Basic Hotspots analysis on the modified code.

    VTune Amplifier collects data and opens the result in the Result tab. Make sure to close the results before comparison.

  2. Select the result in the Project Navigator, right-click and choose Compare Results from the context menu.

    The Compare Results window opens.

  3. Specify the Basic Hotspots analysis results you want to compare and click the Compare Results button:

    The Hotspots Summary window opens, providing a high-level picture of performance improvements in the following format: <result 1 value> - <result 2 value>.

Identify the Performance Gain

In the Summary window, you see that the Elapsed time shows 19.633 seconds of optimization for the whole application execution:

The Top Hotspots section shows the gain in performance for the most critical functions:

Switch to the Bottom-up window to compare the two results and see the differences per metrics side by side.

See Also

For more complete information about compiler optimizations, see our Optimization Notice.