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
Persistent Memory 7
Persistent Memory (PMem), also known as Non-Volatile Memory (NVM), is capable of maintaining data
even after a power outage. PMem can be used by applications that are sensitive to downtime and require
high performance.
VMs can be configured to use PMem on a standalone host, or in a cluster. PMem is treated as a local
datastore. Persistent memory significantly reduces storage latency. In ESXi you can create VMs that are
configured with PMem, and applications inside these VMs can take advantage of this increased speed.
Once a VM is initially powered on, PMem is reserved for it regardless of whether it is powered on or off.
This PMem stays reserved until the VM is migrated or removed.
Persistent memory can be consumed by virtual machines in two different modes. Legacy guest OSes can
still take advantage of virtual persistent memory disk feature.
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Virtual Persistent Memory (vPMem)
Using vPMem, the memory is exposed to a guest OS as a virtual NVDIMM. This enables the guest
OS to use PMem in byte addressable random mode.
Note You must use VM hardware version 14 and a guest OS that supports NVM technology.
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Virtual Persistent Memory Disk (vPMemDisk)
Using vPMemDisk, the memory can be accessed by the guest OS as a virtual SCSI device, but the
virtual disk is stored in a PMem datastore.
When you create a VM with PMem, memory is reserved for it at the time of Hard disk creation. Admission
control is also done at the time of Hard disk creation.
In a cluster, each VM has some capacity for PMem. The total amount of PMem must be greater than the
total amount available in the cluster. The consumption of PMem includes both powered on and powered
off VMs. If a VM is configured to use PMem and you do not use DRS, then you must manually pick a host
that has sufficient PMem to place the VM on.
NVDIMM and traditional storage
NVDIMM is accessed as memory. When you use traditional storage, software exists between applications
and storage devices which can cause a delay in processing time. When you use PMem, the applications
use the storage directly. This means that PMem performance is better than traditional storage. Storage is
local to the host. However, since system software cannot track the changes, solutions such as backups
and HA do not currently work with PMem.
VMware, Inc.
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