A Comparative Study of Parallel and
Robert Ro
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Abstract
Priority queues are used in many applications including real-time systems, operating systems, and simulations. Their implementation may have a profound effect on the performance of such applications. In this article, we study the performance of well-known sequential priority queue implementations and the recently proposed parallel access priority queues. To accurately assess the performance of a priority queue, the performance measurement methodology must be appropriate. We use the Classic Hold, the Markov Model, and an Up/Down access pattern to measure performance and look at both the average access time and the worst-case time that are of vital interest to real-time applications. Our results suggest that the best choice for priority queue algorithms depends heavily on the application. For queue sizes smaller than 1,000 elements, the Splay Tree, the Skew Heap, and Henriksen's algorithm show good average access times. For large queue sizes of 5,000 elements or more, the Calendar Queue and the Lazy Queue offer good average access times but have very long worst-case access times. The Skew Heap and the Splay Tree exhibit the best worst-case access times. Among the parallel access priority queues tested, the Parallel Access Skew Heap provides the best performance on small shared memory multiprocessors.
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I would like to express my deep appreciation to my advisor, Dr. Baker without whose constant support and encouragement, this project would not have seen completion. His original ideas, comments and suggestions were invaluable to me at all times. I also wish to thank my committee members, Dr. Lacher and Dr. Van Engelen for spending their time and effort reviewing this report. I am grateful to Mr. Gaitros, who has been very helpful to me by lending me the resources needed to complete this work. My sincerest gratitude goes to my friends, peers and colleagues, Bharath Allam, Nikhil Iyer, and Nikhil Patel, who were constantly with me with their suggestions and support. I wish to thank Smita Bhatia for her immense patience and inexhaustible support, and my parents, Shaila and Jayprakash for bearing with me through this considerable length of time Last but not the least, a special thanks goes to Douglas Adams for helping me understand the concept of the Babel fish.
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