What do shares establish in resource allocation?

Shares are a mechanism used in VMware vSphere to define resource allocation among virtual machines in a way that ensures fairness and efficiency. When virtual machines are assigned shares, they determine their relative priority for accessing resources like CPU and memory. This means that if multiple VMs are competing for the same resources, the VM with more shares gets a higher priority and will receive a larger portion of the resource compared to those with fewer shares.

This relative allocation ensures that resources are distributed according to the needs of the workloads and their importance to the overall environment. For example, a VM that is critical to business operations might be assigned more shares, ensuring it receives the necessary resources even during peak usage times when demand is high.

The concept of relative priority is fundamental to how vSphere manages resources dynamically. It adapts allocation based on current demand, rather than using a fixed amount or a different scheme that could lead to inefficient resource use. This sensitivity to the number of shares enables a responsive and adaptable environment that aligns resource distribution with the operational requirements of the VMs.