Configuring repository caching

You can configure a caching functionality on your repositories. When caching is enabled on a repository, the system saves the content of the repository (dashboards, queries, visual reports, and other objects) to the memory on the workstation client or on on the web server if you are using QMF for WebSphere®.

1. Open the second page of the Creating New Repository Connection wizard or of the Edit Repository Connection wizard.
2. In the Repository cache area, select the Enable check box to activate cache configuration options.

   The radio buttons for predefined cache validation are enabled in the Predefined modes section.

   To implement a predefined cache validation mode, select the associated radio button. The cache validation processing for each predefined mode are as follows:

   • Low relevance-High performance

     If selected, cache validation is not performed.

   • Balanced relevance/performance

     If selected cache validation is performed every 5 minutes. This is the default setting for cache validation.

   • High relevance-Low performance

     If selected cache validation is performed every 60 seconds (1 minute).

3. To implement custom cache validation, select the Use custom cache settings check box.

   When you select the Use custom cache settings check box, the options for predefined cache validation modes are disabled.

   Click Custom. . . to launch the Repository Cache Settings wizard.

   Use this wizard to specify cache size information and to set validation intervals.

   The wizard consists of two panes:

   • The Repository Caches pane on the left

     This pane lists the specific types of repository-related data to cache.

   • The Repository Caches Settings pane on the right

     This pane is where you set the caching parameters.

     You can set parameter values for general caching, which are applied to each type of repository-related data.

     You can also set parameter values for the different types of repository-related data. These types include:

     • Content Cache

     • Server Metadata Cache
     • Structure Cache
     • Table Metadata Cache
   1. To set general cache settings, click Repository Caches in the list pane and set a value in the Cache validation time (minutes) field.

      The value you enter represents how often (in minutes) that cache validation occurs.

      The value you enter determines how often the cache validates that the objects in it haven't changed. The system checks the last updated date for every cached object stored in the repository.

      The default value is 5 minutes.

      Any object that has been changed gets removed from the cache.

      Any object that has not been accessed within the time specified, are not removed from the cache.

      Enter 0 (zero) if you never want to refresh the cache. This is useful for repositories with static content.

   2. To set parameter values for the different types of repository-related data, expand Repository Caches and select the type of data to configure.
      The types of repository-related data and their configuration parameters are as follows:

      • Content Cache
        Includes the following parameter:

        • Content size (megabytes) specifies the maximum size allowed (in megabytes) for cached content.

          The value entered represents the total combined size of all objects stored in the cache and saved to memory on your machine if you are using QMF for Workstation and on the web server if you are using QMF for WebSphere.

          When a new object is added to the cache whose size has reached the maximum allowed size, the system removes objects until it has enough space to accommodate the new object.

          Those objects that have not been accessed for the longest period of time are removed first.

      • Server Metadata Cache
        Includes the following parameters:

        • Lifetime limit (minutes)

          Parameter sets maximum time (in minutes) for records to be kept in cache. Lifetime is calculated for each record starting from the moment of its creation. Upon expiration of specified lifetime record is forced out of cache.

        • Inactivity (minutes)

          Parameter sets maximum time (in minutes) for records to be kept in cache without being referenced. Inactivity period is calculated for each record starting from the moment of its last use. Upon expiration of specified inactivity period record is forced out of cache.

      • Structure Cache
        Includes the following parameters:

        • Lifetime limit (minutes)

          Parameter sets maximum time (in minutes) for records to be kept in cache. Lifetime is calculated for each record starting from the moment of its creation. Upon expiration of specified lifetime record is forced out of cache.

        • Inactivity (minutes)

          Parameter sets maximum time (in minutes) for records to be kept in cache without being referenced. Inactivity period is calculated for each record starting from the moment of its last use. Upon expiration of specified inactivity period record is forced out of cache.

      • Table Metadata Cache
        Includes the following parameters:

        • Lifetime limit (minutes)

          Parameter sets maximum time (in minutes) for records to be kept in cache. Lifetime is calculated for each record starting from the moment of its creation. Upon expiration of specified lifetime record is forced out of cache.

        • Inactivity (minutes)

          Parameter sets maximum time (in minutes) for records to be kept in cache without being referenced. Inactivity period is calculated for each record starting from the moment of its last use. Upon expiration of specified inactivity period record is forced out of cache.

4. Click Finish to exit the wizard.