Identifying phases of program execution

Periods of computation and periods of inactivity in the execution of a program can be easily identified using the Execution Flow view of the Profiling Tool. Prerequisites:

• Launching or attaching to an application

• In specifying profiling criteria, the Execution History - Full Graphical Detail profiling set is selected or the Time Analysis with Show execution flow graphical details profiling set is enabled in a custom profiling set.

To open the Execution Flow view:

1. Select either the monitor or the agent resource in the Profiling Monitor view. 

2. Right click, then select Open With > Execution Flow. The Execution Flow view opens.

 

Identifying inactive periods

Inactive periods are those with no active threads; on the graph, an inactive period is one with no colored bars.  Read time (in seconds) along the right side. You can also see time in the status line.

Program shutdown would be indicated by the bottom of the bar corresponding to main--if the program was still being monitored.

 

Identifying computation

To examine the flow of execution during computation, follow these steps:

1. Click the Zoom In tool  to enable it, then use the tool to enlarge a sequence of method calls in main.

2. Alternately, click the Select Zoom tool and then click and drag the mouse pointer to enlarge an area.

3. Move the cursor over any method's stripe and view details about it in the status line.

Related concepts
Overview of the Profiling Tool
Execution flow view and table

Related tasks
Profiling an application
Launching or attaching a Java process
Identifying active threads
Tutorial: Analyzing the profiling data from a Java process

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