21.1 Introduction

The Profiler provides a way of monitoring Lisp functions during the execution of your code. It is likely that you can make your code more efficient using the data that the Profiler displays.

The Profiler helps you to identify functions which are called frequently or are particularly slow. You should concentrate your optimization efforts on these routines.

To create a Profiler, choose Tools > Profiler or click in the Podium.

Figure 21.1 The Profiler

The Profiler has several areas. The Code to Profile panel lets you set up and profile any amount of Lisp source code.

• Use the large text box to enter the Lisp source code that you wish to profile. This text area is actually an editor window, similar to those described in Basic editor commands.
• The Symbols... and Packages... buttons let you choose which symbols and packages you want to profile.
• The Profile button runs and profiles the source code you entered.

The Results area is used to display the results of a profile.

• The main list displays the functions called during the last profile. For each function, the list displays the number of calls, the number of times it was found on the stack, and the number of times it was found at the top of the stack.
• The Filter box lets you restrict the display of information in the Results area.
• The Profile Summary box provides a summary of the last profile performed.

In The Profiler, the Packages button was first used to view the package filter selection dialog box (shown in Figure 18.3); all packages except from COMMON-LISP-USER were deselected. By default, all packages are selected. When trying to profile code without a user interface, it is useful to deselect the package CAPI.

You can add a description area by clicking on the Description >> button. The Description area provides a description of any item selected in the Results area, giving you the name, function, lambda list, documentation string and source files of the selected item. Hide the description area if you wish by clicking on the Description << button