The majority of the information generated by dump analysis is stored in the user dump directory, which is a data set allocated to the ddname IPCSDDIR. The user dump directory contains information, called a source description, used by IPCS to process dumps, traces, and other sources efficiently.

The source descriptions resemble a notebook that IPCS uses as it processes a source; IPCS writes notes about the dump, such as its symbols, the location of control blocks, and session defaults. Later, when IPCS needs some information from its notes to format a dump, IPCS obtains it from the source description for the dump.