5.2

2 When you create a new desktop pool or edit an existing pool, navigate to the Select Datastores page.
Option Action
New desktop pool
a Click Add.
b
Proceed through the Add Pool wizard until the Select Datastores page
is displayed.
Existing desktop pool
a Select the linked-clone pool and click Edit.
b
Click the vCenter Settings tab.
3
On the Select Datastores page, select the storage overcommit level.
Option Description
None
Storage is not overcommitted.
Conservative
4 times the size of the datastore. This is the default level.
Moderate
7 times the size of the datastore.
Aggressive
15 times the size of the datastore.
4
Click Done.
5 Click Finish.
Storage Overcommit for Linked-Clone Desktops
With the storage overcommit feature, you can reduce storage costs by placing more linked-clone desktops on
a datastore than is possible with full virtual-machine desktops. The linked clones can use a logical storage
space several times greater than the physical capacity of the datastore.
This feature helps you choose a storage level that lets you overcommit the datastore's capacity and sets a limit
on the number of linked clones that View Manager creates. You can avoid either wasting storage by
provisioning too conservatively or risking that the linked clones will run out of disk space and cause their
desktop applications to fail.
For example, you can create at most ten full virtual machines on a 100GB datastore, if each virtual machine is
10GB. When you create linked clones from a 10GB parent virtual machine, each clone is a fraction of that size.
If you set a conservative overcommit level, View Manager allows the clones to use four times the physical size
of the datastore, measuring each clone as if it were the size of the parent virtual machine. On a 100GB datastore,
with a 10GB parent, View Manager provisions approximately 40 linked clones. View Manager does not
provision more clones, even if the datastore has free space. This limit keeps a growth buffer for the existing
clones.
Table 5-12 shows the storage overcommit levels you can set.
Table 5-12. Storage Overcommit Levels
Option Storage Overcommit Level
None Storage is not overcommitted.
Conservative 4 times the size of the datastore. This is the default level.
Moderate 7 times the size of the datastore.
Aggressive 15 times the size of the datastore.
Storage overcommit levels provide a high-level guide for determining storage capacity. To determine the best
level, monitor the growth of linked clones in your environment.
Set an aggressive level if your OS disks will never grow to their maximum possible size. An aggressive
overcommit level demands attention. To make sure that the linked clones do not run out of disk space, you
can
periodically refresh or rebalance the desktop pool and reduce the linked clones' OS data to its original size.
Chapter 5 Creating Desktop Pools
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