If you have a Fully Managed VPS, you can manage the CPU, Memory, and I/O resources.
  1. Log in to WHM.
  2. Click on CloudLinux Manager under Plugins.
  3. Click on the Users tab.
  4. Click on the pencil icon next to the user you want to change limits for that user.
  5. Input the limits you would like to set on that user, then click Save.
There is no need to restart the server or any services running on the server to apply these limits.

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CPU Settings

Please be advised that CPU limits are set in percentages. For example, 100% is equivalent to 1 CPU core, and 200% CPU is equivalent to 2 CPU cores.