6.0.2

Availability Considerations for Storing Replicas on a Separate Datastore or
Shared Datastores
You can store View Composer replicas on a separate datastore or on the same datastores as linked-clone
virtual machines. These configurations affect the availability of the pool in different ways.
When you store replicas on the same datastores as linked clones, to enhance availability, View Composer
creates a separate replica on each datastore. If a datastore becomes unavailable, only the linked clones on
that datastore are affected. Linked clones on other datastores continue to run.
When you store replicas on a separate datastore, all linked clones in the pool are anchored to the replicas on
that datastore. If the datastore becomes unavailable, the entire pool is unavailable.
To enhance the availability of the linked-clone virtual machines, you can configure a high-availability
solution for the datastore on which you store the replicas.
Configure View Storage Accelerator for Desktop Pools
You can configure desktop pools to enable ESXi hosts to cache virtual machine disk data. This feature, called
View Storage Accelerator, uses the Content Based Read Cache (CBRC) feature in ESXi hosts. View Storage
Accelerator can reduce IOPS and improve performance during boot storms, when many machines start up
or run anti-virus scans at once. The feature is also beneficial when administrators or users load applications
or data frequently. To use this feature, you must make sure that View Storage Accelerator is enabled for
individual desktop pools.
View Storage Accelerator is enabled for a pool by default. You can enable or disable View Storage
Accelerator when you create or edit a pool.
You can enable View Storage Accelerator on pools that contain linked clones and pools that contain full
virtual machines.
View Storage Accelerator is now qualified to work in configurations that use View replica tiering, in which
replicas are stored on a separate datastore than linked clones. Although the performance benefits of using
View Storage Accelerator with View replica tiering are not materially significant, certain capacity-related
benefits might be realized by storing the replicas on a separate datastore. Hence, this combination is tested
and supported.
When a virtual machine is created, View indexes the contents of each virtual disk file. The indexes are stored
in a virtual machine digest file. At runtime, the ESXi host reads the digest files and caches common blocks of
data in memory. To keep the ESXi host cache up to date, View regenerates the digest files at specified
intervals and when the virtual machine is recomposed. You can modify the regeneration interval.
Prerequisites
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Verify that your vCenter Server and ESXi hosts are version 5.0 or later.
In an ESXi cluster, verify that all the hosts are version 5.0 or later.
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Verify that the vCenter Server user was assigned the Global > Act as vCenter Server privilege in
vCenter Server. See the topics in the View Installation documentation that describe View and View
Composer privileges required for the vCenter Server user.
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Verify that View Storage Accelerator is enabled in vCenter Server. See the View Administration
document.
Chapter 15 Reducing and Managing Storage Requirements
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