Sometimes, it is hard to know how much memory and CPU a VM needs. Even when capacity planning is performed, the VM will never use the full memory and CPU specification, resulting in poor memory utilization and a loss of CPU resources.

Windows Server 2008 R2 SP1 introduced a new feature, called Dynamic Memory (DM), which allows the memory on the host server to be shared with the VMs using a method called Ballooning. Ballooning ensures that the VMs use only the memory that they need, and releases it back to the host if another VM requires more memory. This allows the memory in the parent partition to be reallocated automatically through the VMs, increasing or decreasing it based on the current workload.

Let's use an example of a VM that was installed and configured to use 16 GB of memory. That is the value that you got from the planning phase. The problem is that the VM will only use 16 GB when a huge workload is created. This stipulation represents less...