System-level computer architecture simulations create large volumes of simulation data to explore alternative architectural solutions. Interpreting and drawing conclusions from this amount of simulation results can be extremely cumbersome. In other domains that also struggle with interpreting large volumes of data, such as scientific computing, data visualization is an invaluable tool. Such visualization is often domain specific and has not become widely studied and utilized for evaluating the results of computer architecture simulations.In this paper, we introduce our novel interactive visualizationtool, called VMODEX, which is developed to support system-level designspaceexploration of MPSoCarchitectures. In our tool, the designspace is modeled as a tree in which both the design parameters and criteria are shown in a single view. VMODEX is able to handle large designspaces and allows designers to look at the data from different perspectives and at multiple levels of abstraction.Due to the exponential designspace in real problems and multiple criteria to be considered, heuristic searching algorithms are often used to trim down a large designspace into a finite set of points and provide the designer a set of tradable solutions with respect to the design criteria. In VMODEX, besides the techniques provided for visualizing the DSE results, additional capabilities are developed to understand the dynamic search behavior of heuristic searching algorithms.