3.5. Application Profilers
Profiling is the process of gathering information about a program's behavior as it executes. You profile an application to determine which areas of a program can be optimized to increase the program's overall speed, reduce its memory usage, etc. Application profiling tools help to simplify this process.
There are three supported profiling tools for use with Red Hat Enterprise Linux 6: SystemTap, OProfile and Valgrind. Documenting these profiling tools is outside the scope of this guide; however, this section does provide links to further information and a brief overview of the tasks for which each profiler is suitable.
SystemTap is a tracing and probing tool that lets users monitor and analyze operating system activities (particularly kernel activities) in fine detail. It provides information similar to the output of tools like netstat, top, ps and iostat, but includes additional filtering and analysis options for the information that is collected.
SystemTap provides a deeper, more precise analysis of system activities and application behavior to allow you to pinpoint system and application bottlenecks.
The Function Callgraph plug-in for Eclipse uses SystemTap as a back-end, allowing it to thoroughly monitor the status of a program, including function calls, returns, times, and user-space variables, and display the information visually for easy optimization.
