6.7
Table Of Contents
- vSphere Resource Management
- Contents
- About vSphere Resource Management
- Getting Started with Resource Management
- Configuring Resource Allocation Settings
- CPU Virtualization Basics
- Administering CPU Resources
- Memory Virtualization Basics
- Administering Memory Resources
- Persistent Memory
- Configuring Virtual Graphics
- Managing Storage I/O Resources
- Managing Resource Pools
- Creating a DRS Cluster
- Using DRS Clusters to Manage Resources
- Creating a Datastore Cluster
- Initial Placement and Ongoing Balancing
- Storage Migration Recommendations
- Create a Datastore Cluster
- Enable and Disable Storage DRS
- Set the Automation Level for Datastore Clusters
- Setting the Aggressiveness Level for Storage DRS
- Datastore Cluster Requirements
- Adding and Removing Datastores from a Datastore Cluster
- Using Datastore Clusters to Manage Storage Resources
- Using NUMA Systems with ESXi
- Advanced Attributes
- Fault Definitions
- Virtual Machine is Pinned
- Virtual Machine not Compatible with any Host
- VM/VM DRS Rule Violated when Moving to another Host
- Host Incompatible with Virtual Machine
- Host Has Virtual Machine That Violates VM/VM DRS Rules
- Host has Insufficient Capacity for Virtual Machine
- Host in Incorrect State
- Host Has Insufficient Number of Physical CPUs for Virtual Machine
- Host has Insufficient Capacity for Each Virtual Machine CPU
- The Virtual Machine Is in vMotion
- No Active Host in Cluster
- Insufficient Resources
- Insufficient Resources to Satisfy Configured Failover Level for HA
- No Compatible Hard Affinity Host
- No Compatible Soft Affinity Host
- Soft Rule Violation Correction Disallowed
- Soft Rule Violation Correction Impact
- DRS Troubleshooting Information
- Cluster Problems
- Load Imbalance on Cluster
- Cluster is Yellow
- Cluster is Red Because of Inconsistent Resource Pool
- Cluster Is Red Because Failover Capacity Is Violated
- No Hosts are Powered Off When Total Cluster Load is Low
- Hosts Are Powered-off When Total Cluster Load Is High
- DRS Seldom or Never Performs vMotion Migrations
- Host Problems
- DRS Recommends Host Be Powered on to Increase Capacity When Total Cluster Load Is Low
- Total Cluster Load Is High
- Total Cluster Load Is Low
- DRS Does Not Evacuate a Host Requested to Enter Maintenance or Standby Mode
- DRS Does Not Move Any Virtual Machines onto a Host
- DRS Does Not Move Any Virtual Machines from a Host
- Virtual Machine Problems
- Cluster Problems
A cluster is a group of hosts. You can create a cluster using vSphere 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 11
Creating a DRS Cluster for more information.
A datastore cluster is a group of datastores. Like DRS clusters, you can create a datastore cluster using
the vSphere 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 13
Creating a Datastore Cluster.
Resource Consumers
Virtual machines are resource consumers.
The default resource settings assigned during creation work well for most machines. You can later edit
the virtual machine settings to allocate a share-based percentage of the total CPU, memory, and storage
I/O of the resource provider or a guaranteed reservation of CPU and memory. When you power on that
virtual machine, the server checks whether enough unreserved resources are available and allows power
on only if there are enough resources. This process is called admission control.
A resource pool is a logical abstraction for flexible management of resources. Resource pools can be
grouped into hierarchies and used to hierarchically partition available CPU and memory resources.
Accordingly, resource pools can be considered both resource providers and consumers. They provide
resources to child resource pools and virtual machines, but are also resource consumers because they
consume their parents’ resources. See Chapter 10 Managing Resource Pools.
ESXi hosts allocate each virtual machine a portion of the underlying hardware resources based on a
number of factors:
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Resource limits defined by the user.
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Total available resources for the ESXi host (or the cluster).
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Number of virtual machines powered on and resource usage by those virtual machines.
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Overhead required to manage the virtualization.
Goals of Resource Management
When managing your resources, you must be aware of what your goals are.
In addition to resolving resource overcommitment, resource management can help you accomplish the
following:
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Performance Isolation: Prevent virtual machines from monopolizing resources and guarantee
predictable service rates.
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Efficient Usage: Exploit undercommitted resources and overcommit with graceful degradation.
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Easy Administration: Control the relative importance of virtual machines, provide flexible dynamic
partitioning, and meet absolute service-level agreements.
vSphere Resource Management
VMware, Inc. 10