Runaway applications can shorten battery runtime, affect performance, and increase heat and fan activity

Runaway applications can cause the processor to work overtime and affect the system in a number of ways. This can affect battery runtime, overall system performance, and fan and heat levels.

  1. Open Activity Monitor (Applications/Utilities).
  2. Select the CPU tab as shown below.
  3. Select All Processes in the pop-up menu:
  4. Select the "% CPU" column:
  5. Look for any application that has taken over the CPU:
  6. If any process is taking more than 70% of the CPU, as shown above, it is considered to be putting a significant load on the system. Processes related to specific applications that continually use a large percentage of CPU while running may do so without being a runaway process. Those processes may simply require a large amount of system resources to function. For example, working on multiple audio tracks in GarageBand may require a large amount of system resources, but its use of system resources should stop after the task is complete or the application is closed.
  7. You may quit the application to stop it from using the CPU, keeping in mind the following:
    • For processes that relate to specific applications, like Safari, iMovie, iPhoto, or third-party applications, you should try to quit the program from within the individual program after saving the content you are working on.
    • For processes that do not relate to a specific application, or for those you cannot identify which application they relate to, save any important documents or projects you are working on. Then, quit the process by selecting the process and clicking the Quit button in the upper-left corner of the window. This should allow you to regain CPU process control. This will force the process to end or restart if it is something the system requires, and may cause you to loose unsaved work.

To prevent runaway processes in the future, be sure to keep OS X, applications, and plug-ins up to date with the latest versions available from Apple or the manufacturer.

Learn more

The following links offer additional information on optimizing your battery:

The links below offer more information on fan and temperature behavior for your Apple Computer:

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