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View CPU activity in Activity Monitor on Mac
To enable viewing in the Dock, choose View > Dock Icon, then select the Show CPU option you want to view.
In the Activity Monitor app on your Mac , do any of the following:
To view processor activity over time, click CPU. The following percentages appear at the bottom of the Activity Monitor window:
System: The percentage of CPU capability that’s being used by processes that belong to macOS.
User: The percentage of CPU capability that’s being used by apps you opened, or by the processes opened by those apps.
Idle: The percentage of CPU capability that’s not being used.
To view current processor activity, choose Window > CPU Usage.
To view recent processor activity, choose Window > CPU History.
To display more columns, choose View > Columns, then choose the columns you want to show.select CPU, Memory, Disk or Network tab to see its performance parameters:
6. Useless Data in Cache.
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