A virtual machine with ESXi 7.0 Update 1 and later compatibility can have up to 768 virtual CPUs. You can change the number of virtual CPUs while your virtual machine is powered off. If virtual CPU hot add 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 powered 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.

If a virtual machine has 128 virtual CPUs or less, you cannot use hot adding to further increase the number of virtual CPUs. To change the number of virtual CPUs beyond that limit, you must first power off the virtual machine. By contrast, if a virtual machine already has more than 128 virtual CPUs, you can use hot adding to further increase the number of virtual CPUs to up to 768.

The maximum number of virtual CPU sockets that a virtual machine can have is 128. If you want to configure a virtual machine with more than 128 virtual CPUs, you must use multicore virtual CPUs.

Important: 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.

Prerequisites

  • If CPU hot add is not enabled, power off the virtual machine before adding virtual CPUs.
  • To hot add multicore CPUs, verify that the virtual machine is compatible with ESXi 5.0 and later.
  • Verify that you have the Virtual Machine.Configuration.Change CPU Count privilege.

Procedure

  1. Right-click a virtual machine in the inventory and select Edit Settings.
  2. On the Virtual Hardware tab, expand CPU.
  3. From the CPU drop-down menu, select the number of cores.
  4. From the Cores Per Socket drop-down menu, select the number of cores per socket and click OK.