Mac OS X: How to check hard drive activity

In this practical tip, we will show you how to check hard drive activity under Mac OS X using on-board tools.

Check disk activity on Mac OS X using the activity meter

You can get a quick overview of the activity of the hard disk with the activity display:

1. Start the activity display via "Programs" -> "Utilities" -> "Activity display". Alternatively, enter "activity indicator" in the Spotlight search and select the appropriate entry.
2. Click the "Hard Disk Activity" button in the lower part of the window.
3. You now get a complete overview of the read / write access as well as a graphical representation of the maximum value of the inputs and outputs as well as the data throughput.

Mac OS X: Check hard disk activity on the terminal

If the activity indicator only provides a cumulative overview of hard drive activity, the following solution provides more detailed data:

1. Open the terminal via "Programs" -> "Utilities" -> "Terminal".
2. Now enter the following command: "sudo iotop -C 5 12". Complete the entry with the Enter key and then answer the password prompt to start the program.
3. The "iotop" command will now carry out a total of 12 queries every 5 seconds and display the result continuously on the screen.
4. The values ​​in the columns UID (UserID), PID (ProcessID), PPID (ProcessID of the higher-level process) and CMD (Command Name of the process) help you to obtain further details about the processes that access the hard disk. Simply look up the corresponding IDs in the process table of the activity display.
5. If you want to end the display output manually, press the key combination [CTRL] - [C].

You can find out more information about the activity display here.