You can configure a virtual machine that runs on an ESXi host 6.0 and later to have up to 128 virtual CPUs. You can change the number of virtual CPUs while your virtual machine is powered off. If virtual CPU hotplug is enabled, you can increase the number of virtual CPUs while the virtual machine is running.

Virtual CPU hot add is supported for virtual machines with multicore CPU support and ESXi 5.0 and later compatibility. When the virtual machine is turned on, and CPU hot add is enabled, you can hot add virtual CPUs to the running virtual machine. You can add only multiples of the number of cores per socket.


When you configure your virtual machine for multicore virtual CPU settings, you must ensure that your configuration complies with the requirements of the guest operating system EULA.


  • If CPU hot add is not enabled, turn off the virtual machine before adding CPUs.

  • To hot add multicore CPUs, verify that the virtual machine compatibility is ESXi 5.0 and later.

  • Required privilege: Virtual Machine > Configuration > Change CPU Count on the virtual machine


  1. Right-click a virtual machine in the inventory and select Edit Settings.
  2. Expand CPU, and select the number of cores from the CPU drop-down menu.
  3. Select the number of cores per socket from the Cores Per Socket drop-down menu.
  4. Click OK.