Analytical performance models are excellent tools for fast performance prediction and can be used effectively for designing and tuning parallel algorithms. However, such models are non-trivial to build, especially when both the application and the system are very complex.

The paper reports on user experience with Tioga, a DBMS centric visualization tool developed at Berkeley. Based on this experience, we have designed Tioga-2 as a direct manipulation system that is more powerful and much easier to program. A detailed design of the revised system is presented, together with an extensive example of its application.

In the work we present a new architecture for visualization systems that is based on data base management system (DBMS) technology. By building on the mechanisms present in a next-generation DBMS, rather than merely on the capabilities of a standard file manager, we show that a simpler and more powerful visualization system can be constructed. We retain the popular "boxes and arrows" programming notation for constructing visualization programs, but add a "flight simulator" model of movement to navigate the output of such programs. In addition, we provide a means to specify a hierarchy of abstracts of data of different types and resolutions, so that a "zoom" capability can be supported. The underlying DBMS support for this system, Tioga, is briefly described, as well as the current state of the implementation.>