Configuring Web Gardens in IIS 6.0
Applies To: Windows Server 2003, Windows Server 2003 with SP1
In worker process isolation mode, you can configure an application pool to be supported by multiple worker processes. An application pool that uses more than one worker process is called a Web garden. (Web gardens are to be distinguished from Web farms, which use multiple servers for a Web site.)
Important
Web gardens can reduce contention for system resources, such as threads, but they can also cause resource contention. For example, if application resources are designed for exclusive access by a single process, such as a flat file used for temporary storage, resource contention can occur between the worker processes within a Web garden. Also, there are documented application characteristics (singletons) for which Web gardens might cause increased contention.
Creating a Web garden for an application pool enhances performance and reliability in the following ways:
Robust processing of requests. When a worker process in an application pool is tied up (for example, when a script engine stops responding), other worker processes can accept and process requests for the application pool.
Reduced contention for resources. When a Web garden reaches a steady state, each new TCP/IP connection is assigned, according to a round-robin scheme, to a worker process in the Web garden. The round-robin scheme smoothes out workloads and reduces contention for resources that are bound to a worker process.
For more information about configuring Web gardens, see Configuring Web Gardens with IIS 6.0.