Virtualization of SAP on Windows: Hyper-V

For support information concerning SAP software running on Hyper-V, see the following SAP notes.

For information about running SAP on Hyper-V, see the following document.

• More and more customers are running SAP applications on Hyper-V. For example, see the Microsoft case studies with SABMiller RUS or Siemens IT Solutions and Services Thailand.
  For other case studies about Microsoft customers running non-SAP applications on Hyper-V, see: http://www.microsoft.com/virtualization/casestudies
• The SAP Microsoft Platform Team in Germany runs development and test systems on Hyper-V. All virtualized systems show high reliability and stability.

Hyper-V on Windows Server 2008 R2 offers new features like Second Level Address Translation (SLAT), live migration, and Dynamic Memory (with SP1). For a list of the new features, see http://www.microsoft.com/windowsserver2008/en/us/hyperv-R2.aspx.

Hyper-V on Windows Server 2012 offers many new features. For more information, see: http://www.microsoft.com/en-us/download/details.aspx?id=29189 and http://www.microsoft.com/en-us/server-cloud/windows-server/server-virtualization.aspx.

For supported SAP applications with Hyper-V on Windows Server 2012 and the support prerequisites, see SAP Note 1753578.

SAP plans to support Windows Server 2008 (R2) and Windows Server 2012 as guest operating system on the Windows Server 2012 Hyper-V hypervisor. Due to Microsoft's restrictions to support of virtual CPUs for the Windows Server 2003 guest operating system on Hyper-V on Windows Server 2012, SAP will not support Windows Server 2003 as guest operating system.

No. If you pin a process that runs inside a VM to a specific CPU, it will be directly pinned to the specified virtual CPU, not to a physical CPU on hypervisor level. This means that setting processor affinity to one specific CPU results in reduced performance by limiting the disposable virtual CPUs.

Yes, as long as you do not run into performance problems inside the VM.
During the sizing process of the server, you should reserve additional CPU resources for peak load times, software updates, or future requirements. As a rule, the server utilization should not exceed 80% over longer periods to make sure that the server can handle the instant workload in a reliable way.
Configuring each virtual machine with some headroom for CPU capacity without over-committing resources leads to under-utilized physical hardware. In general, appropriate over-commitment of CPUs with regard to the overall load of the server does not lead to a performance impact as long as the peak usage of CPU capacity for all concurrent virtual machines does not occur at the same point in time.
However, if you need to achieve a reliably predictable response time of CPU-bound queries, it is best not to use CPU over-commitment.

With Windows Server 2008 R2 SP1, Microsoft added the Dynamic Memory feature to Hyper-V. The SAP NetWeaver Application Server currently cannot deal with changing resources on operating system level and therefore Dynamic memory is not supported with these applications.  For more information about Hyper-V Dynamic Memory, and its key figures in SAP monitoring,  see the following table:

I want to automate the administration of Hyper-V clients. Are there any helpful tools available?

What about support of an SAP system virtualized on Hyper-V running in a Linux guest?