While Oracle systems could now continue to scale, profiling a session became messy. Now that a server process could process requests from multiple clients, associating a server process activity with a specific client or a specific end user became nearly impossible without specialized tools. This core challenge remains today.

There was another force beginning to rise. As developers began to enrich the user experience and shift processing requirements away from limited database server resources, the capacity of desktop PCs increased. IT budgets started to suffer because of increased operating system and application software licenses, physical hardware costs, security-related issues, and all the related maintenance requirements.

Figure 5-17. To enable Oracle database servers to handle an increasing number of end users, Oracle created server processes that could be shared among client processes. This was brilliant design, because in an OLTP environment, server processes remain very idle.