The Bottom Line
Describe how the resources of a virtual machine are virtualized by the
hypervisor. The hypervisor directly manages the processor and memory resources
with Hyper-V. Logical processors are scheduled to satisfy computer requirements
of virtual processors assigned to virtual machines. Multiple virtual processors can
share the same logical processor. Virtual machines are assigned memory by the
hypervisor from the memory available in the physical host. Dynamic Memory
allows memory to be added and removed from a virtual machine based on resource
need. Other types of resources, such as network and storage, are provided by the
management partition through a kernel mode memory bus known as a VMBus.
This allows existing Windows drivers to be used for the wide array of storage and
network devices typically used.
Master It How is Dynamic Memory different from Memory Overcommit?
Correctly use processor and memory advanced configuration options.
The compatibility configuration of a virtual machine processor should be used
when a virtual machine may be moved between hosts with different versions of the
same processor family. The processor compatibility option hides higher-level
features from the guest operating system, enabling migrations without downtime
to the virtual machine. Processor reserve and limit options ensure that a virtual
machine coexists with other virtual machines without getting too many or too few
resources. Dynamic Memory configurations allow the startup, minimum, and
maximum amounts of memory for a virtual machine to be configured. It’s
important to note that the maximum amount of memory configured is available
only if sufficient memory exists within the host.
Master It When should the NUMA properties of a virtual machine be modified?
Explain the difference between VHD/VHDX and pass-through storage.
VHD and VHDX files are virtual hard disks that are files on a filesystem or share
accessible to the Hyper-V host. They provide abstraction of the storage seen by the
virtual machine and the underlying physical storage. Pass-through storage directly
maps a virtual machine to a physical disk accessible from the host, which limits
Hyper-V functionality and breaks one of the key principles of virtualization: the
abstraction of the virtual machine from the physical fabric.
Master It Why would VHD still be used with Windows Server 2012 Hyper-V?