How to open the Task Manager on Mac and monitor load

Similarly to the Windows equiv­a­lent, in the Apple Task Manager you can easily close programs that are frozen or hanging. But if you want more details about a problem, you’ll need to open the Mac Activity Monitor. This lets you kill unused or un­re­spon­sive ap­pli­ca­tions, and consult sta­tis­tics on CPU and memory load, and energy use. But how do you open the Task Manager on a Mac? And what in­for­ma­tion is shown in the Activity Monitor? We’ve put together a step-by-step guide to help you out.

The Mac Task Manager is a mini-version of the Activity Monitor. To open it, si­mul­ta­ne­ous­ly press down the [CMD] + [ALT] + [ESC] keys on your keyboard. This will open a window con­tain­ing a list of all currently opened programs and ap­pli­ca­tions that are running in the back­ground. Select the program or ap­pli­ca­tion that has frozen and click on the “Force Quit” button to close it.

Like the Task Manager, the Mac Activity Monitor also lists all of the processes that are running on the system. You can open it by going into Ap­pli­ca­tions and selecting Utilities, or searching for it directly in Spotlight by clicking on the mag­ni­fy­ing glass in the upper-right corner of the menu bar.

The Mac Activity Monitor is split into several sections: CPU, Memory, Energy, Disk, Network, and (in later versions) Cache. The list of processes includes user apps, system apps used by the operating system, and invisible back­ground processes. You can choose which columns to display and filter the processes by going into the “View” menu. As well as the Mac Activity Monitor, you can also install other programs such as htop to manage system processes.

The “CPU” pane shows how different processes are affecting CPU per­for­mance. Alongside the stats in the “Energy” pane, this in­for­ma­tion can help you work out what processes are affecting the per­for­mance, battery runtime, tem­per­a­ture and fan activity of your Mac. Just below the main window, you will see an ad­di­tion­al section con­tain­ing the following in­for­ma­tion:

• System: Per­cent­age of CPU ca­pa­bil­i­ty currently being used by system processes.
• User: Per­cent­age of CPU ca­pa­bil­i­ty currently being used by apps or processes launched by the user.
• Idle: Per­cent­age of CPU ca­pa­bil­i­ty not in use.
• CPU Load: Per­cent­age of CPU ca­pa­bil­i­ty currently being used by all processes (System and User combined).
• Threads: Total number of threads used across all processes.
• Processes: Total number of processes that are currently running.

The Memory pane of the Mac Activity Monitor tells you how memory is currently being used. The section at the bottom shows the following sta­tis­tics:

• Memory Pressure: This is a graph that il­lus­trates the avail­abil­i­ty of memory resources.
• Physical Memory: Total amount of RAM installed.
• Memory Used: Total amount of RAM currently in use.
• App Memory: Total amount of memory currently being used by apps and their processes.
• Wired Memory: Memory that cannot be com­pressed or paged out to the hard drive and that must therefore remain in RAM.
• Com­pressed: Amount of RAM that is com­pressed to make space for other processes.
• Swap Used: Space that the memory man­age­ment system of the OS is using on your startup drive.
• Cached Files: Memory that was recently used by apps but is now available to other apps.

The “Energy” pane provides in­for­ma­tion on overall energy use and tells you how much energy is being used by each app. As in the other views, you can click the column headings to sort the processes according to the values measured. The bottom pane shows the following:

The “Disk” pane shows how much data each process has read from or written to your disk. It also shows “reads in” and “writes out” (IO), that is, the number of times your Mac accesses the disk to read and write data. The in­for­ma­tion at the bottom of the “Disk” pane shows the total disk activity for all processes combined.

In macOS High Sierra 10.13.4 or later, the Activity Monitor has an ad­di­tion­al pane called “Cache” (if Content Caching is enabled in the “Sharing” pane of System Pref­er­ences). This pane shows in­for­ma­tion such as how much cached content local network devices have uploaded, down­loaded or dropped over time.