6.5.1

Table Of Contents
You can now add CPUs even if the virtual machine is turned on.
Change the Number of Virtual CPUs
You can configure a virtual machine that runs on an ESXi host 6.5 and later to have up to 128 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.
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
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If CPU hot add is not enabled, turn off the virtual machine before adding virtual CPUs.
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To hot add multicore CPUs, verify that the virtual machine is compatible with ESXi 5.0 and later.
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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 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.
Allocate CPU Resources in the VMware Host Client
To manage workload demands, you can change the amount of CPU resources allocated to a virtual
machine by using the shares, reservations, and limits settings.
A virtual machine has the following user-defined settings that affect its CPU resource allocation.
Limit Places a limit on the consumption of CPU time for a virtual machine. This
value is expressed in MHz or GHz.
Reservation Specifies the guaranteed minimum allocation for a virtual machine. The
reservation is expressed in MHz or GHz.
Shares Each virtual machine is granted CPU shares. The more shares a virtual
machine has, the more often it receives a time slice of a CPU when there is
no CPU idle time. Shares represent a relative metric for allocating CPU
capacity.
vSphere Virtual Machine Administration
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