First the UFO list is checked to see if this request has already been rejected once by the system and is to be rejected again.

The application then looks in the main memory of the ICM server cache (memory cache), and icm/HTTP/server_cache_<xx>/memory_size_MB establishes the size of the part of the ISC in main memory.

The application then looks for the object in the file on the hard disk that the ISC is using (disk cache). The icm/HTTP/server_cache_<xx>/size_MB parameter establishes the total size of the ISC (a part of which is instantly accessible as it is stored in main memory).