How is a VM’s CPU and Memory Reservation defined?

A VM's CPU and Memory Reservation is defined as a guarantee of a specific amount of resources to a virtual machine. When a reservation is set, the specified CPU and memory resources are ensured to be available to the VM at all times, regardless of the overall resource demand on the host system. This means that even if there are other VMs running that also require resources, the resources that are reserved for this particular VM will not be taken away, thus ensuring a baseline performance level.

This is particularly important in environments where performance consistency is critical, such as for applications that require dedicated resources to function properly or for mission-critical workloads. Reservations provide a way to manage resources effectively, allowing administrators to ensure that specific VMs have the required resources allocated to them consistently.

The context of other options highlights that choices around maximum limits, temporary allocations, or prioritization during contention address different aspects of resource management within VMware environments. However, the defining feature of reservation is its role in guaranteeing resource availability, making it a crucial aspect of VM performance management.