Introduction to Resource Management

An ESX/ESXi host allocates each virtual machine a portion of the underlying hardware resources based on several factors:

■	Total available resources for the ESX/ESXi host, resource pool, or cluster to which the virtual machine belongs.

■	Number of virtual machines powered on and resource usage by those virtual machines.

■	Overhead required to manage the virtualization.

■	Limits defined by the user.

Resource management allows you to dynamically allocate resources to virtual machines so that you can more efficiently use available capacity. You can change resource allocation in the following ways.

■	Specify resource allocation for individual virtual machines. See CPU and Memory Resource Allocation.

■	Create a hierarchy of resource pools and add the virtual machine to a resource pool with characteristics appropriate for its use. See Resource Pool Hierarchies.

■	Add hosts and virtual machines to a cluster so you can take advantage of VMware DRS for recommendations or automatic resource redistribution. See Creating and Configuring Clusters.