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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
Memory Virtualization Basics 5
Before you manage memory resources, you should understand how they are being virtualized and used
by ESXi.
The VMkernel manages all physical RAM on the host. The VMkernel dedicates part of this managed
physical RAM for its own use. The rest is available for use by virtual machines.
The virtual and physical memory space is divided into blocks called pages. When physical memory is full,
the data for virtual pages that are not present in physical memory are stored on disk. Depending on
processor architecture, pages are typically 4 KB or 2 MB. See Advanced Memory Attributes.
This chapter includes the following topics:
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Virtual Machine Memory
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Memory Overcommitment
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Memory Sharing
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Memory Virtualization
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Support for Large Page Sizes
Virtual Machine Memory
Each virtual machine consumes memory based on its configured size, plus additional overhead memory
for virtualization.
The configured size is the amount of memory that is presented to the guest operating system. This is
different from the amount of physical RAM that is allocated to the virtual machine. The latter depends on
the resource settings (shares, reservation, limit) and the level of memory pressure on the host.
VMware, Inc.
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