5.2

Optimizing Windows 7 and Windows 8 for Linked-Clone Desktops
By
disabling certain Windows 7 or Windows 8 services and tasks, you can reduce the growth of View Composer
linked-clone desktops. Disabling certain services and tasks can also result in performance benefits for full
virtual machines.
Benefits of Disabling Windows 7 and Windows 8 Services and Tasks
Windows 7 and Windows 8 schedule services and tasks that can cause View Composer linked clones to grow,
even when the linked-clone desktops are idle. The incremental growth of linked-clone OS disks can undo the
storage savings that you achieve when you first create the linked-clone desktops. You can reduce linked-clone
growth by disabling these Windows services.
Windows 7 and Windows 8 introduce new services and schedules older services, such as disk defragmentation,
to run by default. These services run in the background if you do not disable them.
Services that affect OS disk growth also generate input/output operations per second (IOPS) on the Windows
7 or Windows 8 virtual machines. Disabling these services can reduce IOPS and improve performance on full
virtual machines and linked clones.
Disabling certain services also might benefit Windows XP and Windows Vista operating systems.
These best practices for optimizing Windows 7 and Windows 8 apply to most user environments. However,
you must evaluate the effect of disabling each service on your users, applications, and desktops. You might
require certain services to stay active.
For example, disabling Windows Update Service makes sense if you refresh and recompose the linked-clone
desktops. A refresh operation restores the OS disks to their last snapshots, deleting all automatic Windows
updates since the last snapshots were taken. A recompose operation recreates the OS disks from a new snapshot
that can contain the current Windows updates, making automatic Windows updates redundant.
If you do not use refresh and recompose regularly, you might decide to keep Windows Update Service active.
Overview of Windows 7 and Windows 8 Services and Tasks That Cause Linked-
Clone Growth
Certain services and tasks in Windows 7 and Windows 8 can cause linked-clone OS disks to grow incrementally
every few hours, even when the linked-clone desktops are idle. If you disable these services and tasks, you can
control the OS disk growth.
Services that affect OS disk growth also generate IOPS on Windows 7 and Windows 8 virtual machines. You
can evaluate the benefits of disabling these services on full virtual machines as well as linked clones.
Before you disable the Windows 7 or Windows 8 services that are shown in Table 4-7, verify that you took the
optimization steps in “Optimize Windows Guest Operating System Performance,” on page 70 and “Optimize
Windows 7 and Windows 8 Guest Operating System Performance,” on page 71.
Chapter 4 Creating and Preparing Virtual Machines
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