Track Your MacBook's Performance with Activity Monitor - dummies

Track Your MacBook’s Performance with Activity Monitor

By Mark L. Chambers

Activity Monitor is specially designed to show you just how hard your CPU, hard drive, network equipment, and memory modules are working behind the scenes. To run Activity Monitor on your MacBook, open the Utilities folder in your Applications folder.

To display each different type of usage, click the tabs in the lower half of the window; the lower pane changes to reflect the desired type. For example, if you click System Memory, you see the amount of unused memory; click CPU or Network to display real-time usage of your MacBook’s CPU and network connections.


You can also display a separate window with your CPU usage; choose Window→CPU Usage or press Command+2. There are three different types of central processing unit (CPU, which is commonly called the “brain” of your MacBook) displays available from Activity Monitor:

  • Floating CPU window: This is the smallest display of CPU usage; the higher the CPU usage, the higher the reading on the monitor. You can arrange the floating window in horizontal or vertical mode from the Window menu.

  • CPU Usage window: This is the standard CPU monitoring window, which uses a blue thermometer-like display. The display works the same as the floating window.

  • CPU History window: This scrolling display uses different colors to help indicate the percentage of CPU time being used by your applications (green) and what percentage is being used by Lion to keep things running (red). You can use the History window to view CPU usage over time.

The CPU usage and history displays can also be displayed in the Dock.

You have multiple bars in your CPU usage monitor because you’re running one of Apple’s multiple-core Intel processors in your MacBook. More than one engine is under the hood

Whichever type of display you choose, you can drag the window anywhere that you like on your Mac OS X Desktop. Use the real-time feedback to determine how well your system CPU is performing when you’re running applications or performing tasks in Mac OS X. If this meter stays peaked for long periods of time while you’re using a range of applications, your processor(s) are running at full capacity.

You can even monitor CPU, network, hard drive, or memory usage right from the Dock! Choose View→Dock Icon; then choose what type of real-time graph you want to display in your Dock. (Feeling like a Lion power user yet?)

When you’re monitoring CPU usage from the Dock, the green portion of the bar indicates the amount of processor time used by application software, and the red portion of the bar indicates the CPU time given to the Mac OS X operating system (same as how this works in the CPU History window).

Note, however, that seeing your CPU capacity at its max doesn’t necessarily mean that you need a faster CPU or a new computer. For example, when running memory-ravenous applications, such as Photoshop or Word, the Activity Monitor on your MacBook Pro is often pegged (indicating maximum use) for several seconds at a time.

It barely moves the rest of the time. Whether a computer is actually fast enough for you and the applications that you run is more of a subjective call on your part.