Citrix Server Test

The DDC allows a user to get a listing of all available applications published in the farm.  This enumeration of resources takes place automatically every time the user launches the Citrix XenDesktop solution. This metric reflects the rate of application enumerations. An unusually high number of enumerations can slow down the XenDesktop.

When the user clicks the link to a published application, the link is resolved to an application. This metric reflects the workload on the server in terms of application accesses. The rate of application resolutions depends on the number of users connecting to the farm, duration for which the average user stays logged on, and the number of published applications. If the rate of application resolutions is excessively high, consider creating multiple zones in the farm to reduce the load on the data collector.

The data store of the DDC hosts centralized configuration data for a server farm. The data store is critical for central administration of the server farm. Hence, any loss of communication between a DDC and its data store can result in inconsistencies in the configuration data. A high value of this measure is hence a cause for concern as it indicates that the DDC has been disconnected from the datastore for a long time.

This metric reports the workload on the data store. Since it is a central repository for a farm, slowdown of the data store can impact the performance of the farm. Data store traffic is usually high during server startup.

This metric reports the workload on the data store. Since it is a central repository for a farm, slowdown of the data store can impact the performance of the farm.

The dynamic store maintains information that changes frequently such as current sessions, disconnected sessions, server load, etc. This metric denotes the read rate of data from the dynamic store.

The dynamic store maintains information that changes frequently such as current sessions, disconnected sessions, server load, etc. This metric denotes the rate at which data is written to the dynamic store.

Each server has a subset of the data store called the local host cache. The local host cache performs two functions:

• It permits the server to function in the absence of a connection to the data store.
• Improves performance by caching information used by ICA clients for enumeration and application resolution.

The larger the cache, greater the hits to the cache and fewer data store accesses. Comparing the read rate from the local host cache and the data store, the administrator can assess the cache efficiency.

Zones in a DDC farm serve two purposes - (a) to collect data from member servers in a hierarchical structure; (b) efficiently distribute changes to all servers in the farm. The first server in a farm is the data collector of the farm by default. Elections within a zone are used to determine the data collector for the zone. Frequent zone elections in a zone can result in increased network traffic.