6.0.1

Table Of Contents
Getting Started with Resource
Management 1
To understand resource management, you must be aware of its components, its goals, and how best to
implement it in a cluster setting.
Resource allocation settings for a virtual machine (shares, reservation, and limit) are discussed, including
how to set them and how to view them. Also, admission control, the process whereby resource allocation
settings are validated against existing resources is explained.
Resource management is the allocation of resources from resource providers to resource consumers.
The need for resource management arises from the overcommitment of resources—that is, more demand
than capacity and from the fact that demand and capacity vary over time. Resource management allows you
to dynamically reallocate resources, so that you can more efficiently use available capacity.
This chapter includes the following topics:
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“Resource Types,” on page 11
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“Resource Providers,” on page 11
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“Resource Consumers,” on page 12
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“Goals of Resource Management,” on page 12
Resource Types
Resources include CPU, memory, power, storage, and network resources.
NOTE ESXi manages network bandwidth and disk resources on a per-host basis, using network traffic
shaping and a proportional share mechanism, respectively.
Resource Providers
Hosts and clusters, including datastore clusters, are providers of physical resources.
For hosts, available resources are the host’s hardware specification, minus the resources used by the
virtualization software.
A cluster is a group of hosts. You can create a cluster using vSphere Web Client, and add multiple hosts to
the cluster. vCenter Server manages these hosts’ resources jointly: the cluster owns all of the CPU and
memory of all hosts. You can enable the cluster for joint load balancing or failover. See Chapter 10,
“Creating a DRS Cluster,” on page 63 for more information.
A datastore cluster is a group of datastores. Like DRS clusters, you can create a datastore cluster using the
vSphere Web Client, and add multiple datstores to the cluster. vCenter Server manages the datastore
resources jointly. You can enable Storage DRS to balance I/O load and space utilization. See Chapter 12,
“Creating a Datastore Cluster,” on page 91.
VMware, Inc.
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