Simultaneous multithreading (SMT) improves processor throughput by processing instructions from multiple threads each cycle. This is the first work to explore soft real-time scheduling on an SMT processor. Scheduling with SMT requires two decisions: (1) which threads to run simultaneously (the co-schedule), and (2) how to share processor resources among co-scheduled threads. We explore algorithms for both for soft-real time multimedia applications, focusing more on co-schedule selection. We examine previous multiprocessor co-scheduling algorithms, including partitioning and global scheduling. We propose new variations that consider resource sharing and try to utilize SMT more effectively by exploiting application symbiosis.We find (using simulation) that the best algorithm uses global scheduling, exploits symbiosis, prioritizes high utilization tasks, and uses dynamic resource sharing. This algorithm, however, imposes significant profiling overhead and does not provide admission control. We propose alternatives to overcome these limitations, but at the cost of schedulability. 1

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Abstract. Several hierarchical clustering techniques have been proposed to visualize large graphs, but fewer solutions suggest a focus based approach. We propose a multilevel clustering technique that produces in linear time a contextual clustered view depending on a user-focus. We get a tree of clusters where each cluster- called meta-silhouette- is itself hierarchically clustered into an inclusion tree of silhouettes. Resulting Multilevel Silhouette Tree (MuSi-Tree) has a specific structure called multilevel compound tree. This work builds upon previous work on a compound tree structure called MO-Tree. The work presented in this paper is a major improvement over previous work by (1) defining multilevel compound tree as a more generic structure, (2) proposing original space-filling visualization techniques to display it, (3) defining relevant interaction model based on both focus changes and graph filtering techniques and (4) reporting from case studies in various fields: co-citation graphs, relateddocument graphs and social graphs. 1

Highly resolved numerical solutions of partial differential equations are important in many areas of science and technology. Only adaptive mesh refinement methods reduce the necessary work sufficiently, allowing the calculation of realistic problems. Block-structured