5 Replies Latest reply on Feb 14, 2017 5:31 PM by vipclubber

    Increasing number of CPUs on Win 2012 R2 VM?

    vipclubber Enthusiast

      I have upgraded to new hardware (HP 360p Gen8 from G7) which gave me more CPU cores. There are now 2 CPUs with 10 cores each.

      However my Windows Server 2012 R2 moving from old hardware was configured to 4 cores. New is ESXi 6.0U2.

      Now I want to see if I can adjust the amount of CPUs for this VM to the maximum. This is a Media Streaming server.

      How can I increase the number of CPUs on Windows 2012 R2 VM without compromising stability?

       

        • 1. Re: Increasing number of CPUs on Win 2012 R2 VM?
          thecloudxpert Enthusiast
          vExpert

          You will need to power down the server to adjust the CPU unless you have enabled Hot-Add of the CPU.

           

          The best place to do this is via the vSphere Web Client or vSphere Host Client rather than the C# fat client.

           

          Windows 2012 should be fine with the change in the number of CPUs but in case you're worried about it, backup the VM first (if you have capacity to do so).

          • 2. Re: Increasing number of CPUs on Win 2012 R2 VM?
            a.p. Guru
            Community WarriorsvExpertUser Moderators

            From my experience with Windows 2012R2, I wouldn't expect issues with increasing the number of vCPUs.

            I'd suggest you just try it. In case it doesn't work you can always reduce the vCPU count again.

            "Now I want to see if I can adjust the amount of CPUs for this VM to the maximum."

            Best practice is to assign resources as required by the guest OS. Remember that increasing the guest resources will also increase the overhead on the host, i.e. the host may require more resources than necessary to handle the guest.


            André

            • 3. Re: Increasing number of CPUs on Win 2012 R2 VM?
              vipclubber Enthusiast

              What are the possible things that could go wrong increasing vCPUs that I should be watching for?

              • 4. Re: Increasing number of CPUs on Win 2012 R2 VM?
                vipclubber Enthusiast

                This is a media streaming server which will require excessive use of CPU.

                2 CPUs at 10 cores each = 20 cores. 4k steaming will require high CPU utilization.

                What would be considered a safe increase?

                 

                If something goes wrong with vCPU increase how would I know it? 

                • 5. Re: Increasing number of CPUs on Win 2012 R2 VM?
                  vipclubber Enthusiast

                  When increasing amount of CPUs what are we actually increasing?

                   

                  Lets consider the following scenario:

                  Processor Sockets: 2

                  Cores per socket: 8

                  Logical processors: 32

                   

                  Also if I use vSphere client to change CPUs it allows me to change :

                  Number of virtual sockets: 2

                  Number of cores per socket: 2

                   

                  but via web browser it shows:

                  Cores per socket: 1 which i can't change

                  and the only part I can modify are the 32 logical processors

                   

                  Please kindly advise...