5.6. Hot Plugging vCPUs

You can hot plug vCPUs. Hot plugging means enabling or disabling devices while a virtual machine is running.

Important

Hot unplugging a vCPU is only supported if the vCPU was previously hot plugged. A virtual machine's vCPUs cannot be hot unplugged to less vCPUs than it was originally created with.
The following prerequisites apply:
  • The virtual machine's Operating System must be explicitly set in the New Virtual Machine or Edit Virtual Machine window.
  • The virtual machine's operating system must support CPU hot plug. See the table below for support details.
  • Windows virtual machines must have the guest agents installed. See Section 3.3.2, “Installing the Guest Agents and Drivers on Windows”.

Procedure 5.16. Hot Plugging vCPUs

  1. Click the Virtual Machines tab and select a running virtual machine.
  2. Click Edit.
  3. Click the System tab.
  4. Change the value of Virtual Sockets as required.
  5. Click OK.

Table 5.1. Operating System Support Matrix for vCPU Hot Plug

Operating System
Version
Architecture
Hot Plug Supported
Hot Unplug Supported
Red Hat Enterprise Linux Atomic Host 7
 
x86
Yes
Yes
Red Hat Enterprise Linux 6.3+
 
x86
Yes
Yes
Red Hat Enterprise Linux 7.0+
 
x86
Yes
Yes
Red Hat Enterprise Linux 7.3+
 
PPC64
Yes
Yes
Microsoft Windows Server 2008
All
x86
No
No
Microsoft Windows Server 2008
Standard, Enterprise
x64
No
No
Microsoft Windows Server 2008
Datacenter
x64
Yes
No
Microsoft Windows Server 2008 R2
All
x86
No
No
Microsoft Windows Server 2008 R2
Standard, Enterprise
x64
No
No
Microsoft Windows Server 2008 R2
Datacenter
x64
Yes
No
Microsoft Windows Server 2012
All
x64
Yes
No
Microsoft Windows Server 2012 R2
All
x64
Yes
No
Microsoft Windows Server 2016
Standard, Datacenter
x64
Yes
No
Microsoft Windows 7
All
x86
No
No
Microsoft Windows 7
Starter, Home, Home Premium, Professional
x64
No
No
Microsoft Windows 7
Enterprise, Ultimate
x64
Yes
No
Microsoft Windows 8.x
All
x86
Yes
No
Microsoft Windows 8.x
All
x64
Yes
No
Microsoft Windows 10
All
x86
Yes
No
Microsoft Windows 10
All
x64
Yes
No