Tips for Focusing Performance Data

Related Topics

 

Quantify provides ways to focus data before, during, and after data collection.

Focus data before you start collection by limiting the scope of data collection in one of the following ways:

§      Control the measurement type that Quantify uses to collects data. Collect data at the line level only for the module that contains the code you are testing. Exclude modules for which you do not want to collect data at all.

§      Use selective instrumentation to limit data collection to include specific classes or modules.

§      Use API functions to control data collection programmatically. For native-compiled code, and Visual Basic programs, use the Quantify API functions.

Focus data while your program is running as follows:

§          Use the tools in the Run Control toolbar to pause data recording, clear data, and take a snapshot of the current data while a program is running.

Focus data after you have collected it in the following ways:

§          Highlight specific categories of function (such as functions for which source code is available) in the Call Graph window.

§          Focus on a specific portion of a program by selecting a function in the Call Graph window, right-clicking, and then selecting Subtree > Focus on Subtree from the shortcut menu.

§          You can easily investigate some "what-if" scenarios to gauge the impact of proposed code changes by selecting a subtree, clicking the right mouse button, and then selecting Subtree > Delete Subtree from the shortcut menu.

§          Simplify complex datasets with filters.

§          You can create filters quickly while working in the Call Graph window by selecting a function, right-clicking, and then selecting a Filter command from the shortcut menu.

§          You can create filters using the Filter Manager to remove functions based on module, function, or measurement type.

§          Quantify saves filters in Quantify filter files (qft) to use again whenever you profile programs.

§          You can choose to retain the time of filtered functions as a component of the function + descendants (F+D) time of their callers, or to delete the time altogether.

§          You can enable or disable multiple filters at one time by selecting the filters in the Filter Manager dialog box, right-clicking, and then selecting Enable or Disable from the shortcut menu.

§          You can use the /FilterFiles command-line option to filter data when profiling programs with /SaveTextData from the command line, or in a test script.

(C) Copyright IBM Corporation 1993, 2009.