6.5.1

8 (Optional) If you selected virtual compatibility mode, select a disk mode to change the way that disks
are affected by snapshots.
Disk modes are not available for RDM disks using physical compatibility mode.
Option Description
Dependent Dependent disks are included in snapshots.
Independent - Persistent Disks in persistent mode behave like conventional disks on your physical
computer. All data written to a disk in persistent mode are written permanently to
the disk.
Independent - Nonpersistent Changes to disks in nonpersistent mode are discarded when you power off or
reset the virtual machine. With nonpersistent mode, you can restart the virtual
machine with a virtual disk in the same state every time. Changes to the disk are
written to and read from a redo log file that is deleted when you power off or reset.
9 Click OK.
Use Disk Shares to Prioritize Virtual Machines
You can change the disk resources for a virtual machine. If multiple virtual machines access the same
VMFS datastore and the same logical unit number (LUN), use disk shares to prioritize the disk accesses
from the virtual machines. Disk shares distinguish high-priority from low-priority virtual machines.
You can allocate the host disk's I/O bandwidth to the virtual hard disks of a virtual machine. Disk I/O is a
host-centric resource so you cannot pool it across a cluster.
Shares is a value that represents the relative metric for controlling disk bandwidth to all virtual machines.
The values are compared to the sum of all shares of all virtual machines on the server.
Disk shares are relevant only within a given host. The shares assigned to virtual machines on one host
have no effect on virtual machines on other hosts.
You can select an IOP limit, which sets an upper bound for storage resources that are allocated to a
virtual machine. IOPs are the number of I/O operations per second.
Procedure
1 Right-click a virtual machine in the inventory and select Edit Settings.
2 On the Virtual Hardware tab, expand Hard disk to view the disk options.
3 In the Shares drop-down menu, select a value for the shares to allocate to the virtual machine.
4 If you selected Custom, enter a number of shares in the text box.
5 In the Limit - IOPs box, enter the upper limit of storage resources to allocate to the virtual machine,
or select Unlimited.
6 Click OK.
Configure Flash Read Cache for a Virtual Machine
You can configure Flash Read Cache for your virtual machine.
vSphere Virtual Machine Administration
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