6.0.1
Table Of Contents
- vSphere Resource Management
- Contents
- About vSphere Resource Management
- Updated Information
- Getting Started with Resource Management
- Configuring Resource Allocation Settings
- CPU Virtualization Basics
- Administering CPU Resources
- Memory Virtualization Basics
- Administering Memory Resources
- View Graphics Information
- 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
- Index
Host-local swap is now enabled for the standalone host.
Swap Space and Memory Overcommitment
You must reserve swap space for any unreserved virtual machine memory (the difference between the
reservation and the configured memory size) on per-virtual machine swap files.
This swap reservation is required to ensure that the ESXi host is able to preserve virtual machine memory
under any circumstances. In practice, only a small fraction of the host-level swap space might be used.
If you are overcommitting memory with ESXi, to support the intra-guest swapping induced by ballooning,
ensure that your guest operating systems also have sufficient swap space. This guest-level swap space must
be greater than or equal to the difference between the virtual machine’s configured memory size and its
Reservation.
CAUTION If memory is overcommitted, and the guest operating system is configured with insufficient swap
space, the guest operating system in the virtual machine can fail.
To prevent virtual machine failure, increase the size of the swap space in your virtual machines.
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Windows guest operating systems— Windows operating systems refer to their swap space as paging
files. Some Windows operating systems try to increase the size of paging files automatically, if there is
sufficient free disk space.
See your Microsoft Windows documentation or search the Windows help files for “paging files.”
Follow the instructions for changing the size of the virtual memory paging file.
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Linux guest operating system — Linux operating systems refer to their swap space as swap files. For
information on increasing swap files, see the following Linux man pages:
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mkswap — Sets up a Linux swap area.
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swapon — Enables devices and files for paging and swapping.
Guest operating systems with a lot of memory and small virtual disks (for example, a virtual machine with
8GB RAM and a 2GB virtual disk) are more susceptible to having insufficient swap space.
NOTE Do not store swap files on thin-provisioned LUNs. Running a virtual machine with a swap file that is
stored on a thin-provisioned LUN can cause swap file growth failure, which can lead to termination of the
virtual machine.
When you create a large swap file (for example, larger than 100GB), the amount of time it takes for the
virtual machine to power on can increase significantly. To avoid this, set a high reservation for large virtual
machines.
You can also place swap files on less costly storage using host-local swap files.
Configure Virtual Machine Swapfile Properties for the Host
Configure a swapfile location for the host to determine the default location for virtual machine swapfiles in
the vSphere Web Client.
By default, swapfiles for a virtual machine are located on a datastore in the folder that contains the other
virtual machine files. However, you can configure your host to place virtual machine swapfiles on an
alternative datastore.
You can use this option to place virtual machine swapfiles on lower-cost or higher-performance storage.
You can also override this host-level setting for individual virtual machines.
vSphere Resource Management
40 VMware, Inc.