Windows 7 and Windows 8 schedule services and tasks that can cause View Composer linked clones to grow, even when the linked-clone machines 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 machines. 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.
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 clones. 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.