Walkthrough - Comparing Performance Data

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After you have identified bottlenecks, make improvements and rerun your code. The fourth and final step in profiling is to compare performance data from the two runs in order to determine the effect of your changes on performance.

To compare your new performance data to your original data, perform a Diff. Highlight the entry for the new run in the Navigator window and click the Diff button images\diffic.gif

The Diff Call Graph highlights performance improvements in green and regressions in red, to help you identify performance changes quickly. The Diff Function List displays the differences between the two runs, as well as original data from the two runs.

Use the Navigator to keep track of all the runs you're working with. You can save performance data as a Quantify data file (.qfy), to use for further analysis or to share with other Quantify users. You can save data to a tab-delimited ASCII text file (.txt) to use outside of Quantify, for example, in test scripts or in Microsoft Excel. You can also copy data directly from the Function List window to use in Excel.

You can also easily analyze the performance of the program over several runs by merging the separate runs to create a new dataset.

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