The reason is that there is a setting in IIS which says that after a configurable period of inactivity the app pool will be recycled. Now the FAQ – Why is the self-service portal so slow? So – the first time that you access the self-service portal after the app pool has been started or recycled it takes a long time to wait for the compile to happen. After that it is very fast because it is using the compiled application. In the case of the SCSM self-service portal it can take about 5-20 seconds. The problem is that this JIT compile process can take a few seconds depending on the size of the site. This makes the application run faster as a compiled application. IIS has a feature called Just In Time (JIT) compiling that will compile a application the first time the app pool it is located in starts up. You can have many applications running in a single app pool which runs as a particular identity and has various other knobs, levers, and switches that allow you to control how the applications in that app pool behave. This web site uses what is called an “app pool” (short for application pool) to run. The self-service portal is built as an ASP.Net web site that runs as an application in Internet Information Services (IIS). First published on TECHNET on May 11, 2011
