The Cache Settings screen is used to set several Cache-related settings of your ColdFusion server:
Template Cache Size
Cold Fusion maintains a cache in memory where the most recently processed templates are kept. When a request is received in the cache, it is accessed from the cache rather than accessing the file and reprocessing the template. This can vastly improve performance at the expense of the use of RAM memory. 1f you have sufficient available memory, consider setting the cache size to the total size of all templates on the server. Then, after they all are processed they will remain in memory and system performance will improve. Keep in mind that if your application handles-live data such as from a rapidly changing database or other data source, you won’t want to cache in order to ensure that the latest data is used each time a template is requested. Also, take care not to overuse RAM with ColdFusion. You may speed up ColdFusion at the expense of all other services on your system.
Trusted Cache If templates on your server are not updated between ColdFusion process restarts, then you can force Cold Fusion to serve files from the cache without checking files for potential updates by enabling this setting. This will minimize file
system-overhead and improve performance of the server but also means that you cannot change templates without restarting ColdFusion.
Limit Database Connection inactive Time
With client-server databases, you can open a connection to the database and then maintain the connection. This can notably improve database performance because each query does not need to open a connection, process the query, and then disconnect. However, maintaining these open ‘connections is done at the expense of making the connection available to other clients. By setting this value to any time greater than zero, ColdFusion will close cached database connections (those that have been kept open) when the connection has been inactive for more than the specified time.
Limit the Maximum Number of Cached Queries
Just as Cold Fusion caches templates, it can also cache the results of queries. The amount of available cache is specified in terms of the number of queries to cache rather than the- amount of Using the ColdFusion Administrator 845 RAM to make available to the cache because of the possibility of widely varying query sizes. When the number of queries is exceeded, the oldest queries are discarded to make way for new ones. Caching of queries requires the use of special attributes in your QUERY tags as outlined in, “Using QUERY and SQL to Interact with the Database.”
The Basic Security screen lets you set several fundamental security settings for your ColdFusion server. Here you can enable and set the password required for accessing the ColdFusion Administrator as well as the password used by users of ColdFusion Studio for accessing the server. Setting the Cold Fusion Administrator password is highly recommended. In addition, you can selectively enable and disable the following tags <FCONTENTC, FDIRECTORYC, FFILE, CFOBJECT,CFREGISTRYC, FADMINSECURITY a, CFEXECUTE
These tags are potential security holes because they provide users on the Web access to data on the server PC outside the scope of the Web server’s document root and, in some cases, even allow for the altering of content on the server. If you restrict access to,the tags outlined above, you can still provide limited access to these tags by specifying a directory in the Unsecured tags directory field. Any templates in this directory will not be subject to the tag limitations you have specified.
The Advanced Security screen is used to configure fine grained security for your ColdFusion applications. This screen is discussed in detail in”Application Security.”
As you learned, “Implementing the Cold Fusion Web Application Framework,” client variables can be stored in several places, including the registry, cookies, or databases through ODBC or native data sources. On the Client Variable Storage screen, shown in Figure 35.3, you can control these aspects of client variables as well as settings related to application and session variables.
For client variables, you can configure a data source for client variable storage by selecting the data source name from the drop-down list and then clicking the Add button. You will then be presented with the Create Client Variable Storage screen like the one in Figure 35.4, where you can finish providing information needed to enable the data source. The information asked for on this screen is: