Measures reported by VmgCtxAppLayerTest

Citrix App Layering lets you package any Windows application as a virtual disk, layer and deliver it, installation-free, to pooled desktops and session hosts. With App Layering, you can:

• Install and manage a single copy of your Windows operating system and a single copy of each of your applications in layers. A layer is simply a container for the file system objects and registry entries unique to that layer.

• Select any combination of layers to create layered Images that are deployable as desktops or session hosts.

• Deploy the layered images to virtual machine desktops and session hosts, making the applications available to users.

Citrix App Layering enables IT administrators to deliver applications that look, act and feel as if they are installed locally in the VM/Golden Image, but these applications are actually stored as separate manageable objects in their own virtual disks. With Citrix App Layering, any application can be separated from the Windows OS. As a result, IT administrators will only have a single OS Layer to manage regardless of the number of machine configurations (pools, silos, delivery groups). This simplifies the environment while reducing management time/complexity and the costs associated with OS and app management. Application layers can be attached to the virtual machine in one of two ways:

1. App Layers can be combined with an OS Layer, in a process called image publishing, and pushed to existing provisioning systems such as Citrix Provisioning Services, Citrix Machine Creation Services, or VMware View Composer;

2. App Layers can be attached to a VM at user login based on user AD group membership and app assignments. Each user can also receive a unique “Personalization Layer.” This Personalization Layer will contain unique information for that user that will include things like local Windows profiles, application settings, files and folders created by the user and even user-installed applications.

The App Layers can be attached to persistent and non-persistent desktops in the VDI environment. A persistent virtual desktop, also known as a dedicated desktop, is a unique operating system image created for each user. The customized App Layers are attached to a user when he/she logs in to the persistent desktop at the very first time. These customized layers and specific settings will be available to the user until he/she reboots the desktop. On the other hand, a non-persistent desktop, also called stateless desktop, cannot be personalized for every user and can be shared among multiple users to the environment. The App Layering makes it possible to save user data and user-installed software even in non-persistent deployments. In non-persistent deployments, the App Layers are attached to every user based on their customization whenever he/she logs in. These layers and the corresponding settings will be available until he/she logs off from the session. Once the user logs out from the non-persistent desktop, the layers will be detached and the desktop will be ready for use by another user.

of the types of virtual desktops to which the App Layering is done, it is important that the App Layers should be fully attached without adding a significant delay to the logon process. If, for any reason, App Layering failed or takes more time during the logon process, then the logon process may fail or take longer time to complete. This in turn will impact the productivity of the users and overall user experience with the virtual server. Particularly, if the users experience frequent delays in the non-persistent environment, then the productivity and experience during every session initiated from the non-persistent desktop will be seriously impacted. Therefore, it is imperative that administrators keep track of the time taken for attaching the App Layers and the layers attached during every user's session. This can be easily tracked using the VmgCtxAppLayerTest test.

This test helps administrators to promptly find out if there is a delay during the App Layering process and enables them to take remedial measures before the delay causes serious impact on the productivity and user experience.

This test is applicable only for the App Layering enabled desktops that are hosted by the ESX server host.

Output of the Test: One set of results for each user to the virtual server that is to be monitored.

Descriptor of the Test: User