IIS applicationsProgramThe pool is a software container.
As the virtual host environment of the program instance.
In Microsoft Windows, a program instance and its allocated resources are called processes.
System resources are allocated to each application pool and shared by the host among the application instances in the application pool.
This model provides a way to share resources between application pools and between processes in the pool.
However, it isolates the processes in one pool from those in another pool.
The application pool is not directly mapped to any hardware location, nor bound to a single CPU or a group of CPUs.
A single CPU can support multiple application pools, and a single application pool can also span multiple CPUs.
Therefore, the application pool isolates its programs from those outside the application pool.
The application and hardware are also isolated.
Therefore, the Sharepoint Server 2007 web application is bound to the application pool, and the application pool serves as the virtual host environment for processing the running results of Web application instances.