why one application pool has 4 worker processes in IIS
An application pool that contains multiple worker processes is called a Web Garden.
Now, I am not sure if those 4 worker processes were set up during the installation of PerformancePoint or if someone else set them up after the installation. Either way, a web garden is good because:
- Provides better application availability by sharing requests between multiple worker process.
- Web garden uses processor affinity where application can be swapped out based on preference and tag setting.
- Less consumption of physical space for web garden configuration.