Figure 2. 8 Task Manager in Logical Processor view showing the physical processors
and logical processor details
Prior to Windows Server 2012 , the various SKUs (editions) of Windows Server had
different capabilities and scalability. This changed with Windows Server 2012.
Windows Server 2012 Standard and Datacenter have the same scalability and
capabilities, supporting up to 320 logical processors addressable by the hypervisor and
4 TB of memory. Each virtual machine can be allocated up to 64 virtual processors.
These scalability numbers did not change with Windows Server 2012 R 2 Hyper-V,
because they didn’t need to. With the Windows Server 2012 Hyper-V scalability
capability of 64 vCPUs per virtual machine, Microsoft found that more than 99
percent of the world’s SQL Server instances could now be virtualized on Hyper-V.
Windows Server 2016 introduces feature differences between the Standard and
Datacenter SKUs, but the scalability is the same for both and remains unchanged from
Windows Server 2012.
Having multiple logical processors is useful for virtualization. To benefit from many
logical processors on a normal system, the applications being used have to be written
to take advantage of multiple threads of execution. Alternatively, many applications
would be used at the same time, and the operating system would distribute them over
the available logical processors. With virtualization, each virtual machine is assigned a
certain number of virtual processors (vCPUs), which then map to logical processors. A
single logical processor can be used by multiple virtual processors, because the logical