 |
|
New approach eliminates software deadlocks using discrete control theory
December 02, 2008ANN ARBOR, Mich.--- Software deadlocks are the Catch-22s of the computer world. These common bugs can freeze the machine when different parts of a program end up in an endless cycle of waiting for one another as they access shared data.
University of Michigan researchers developed a new way around this problem with a controller that can anticipate and prevent situations that might cause deadlock.
Their controller is called Gadara. It's a plug-in that operates using feedback techniques similar to those that give us cruise control in cars and thermostats in heating systems.
"This is a totally different approach to what people had done before for deadlock. Previously, engineers would try to identify potential deadlocks through testing or program analysis and then go back and rewrite the program. The bug fixes were manual, and not automatic. Gadara automates the process," said Stéphane Lafortune, a professor in the Department of Electrical Engineering and Computer Science and a Gadara developer.
Yin Wang, a doctoral student who works with Lafortune in the same department, will present a paper on Gadara Dec. 9 at the USENIX Symposium on Operating Systems Design and Implementation in San Diego.
"Every time you find a problem today you need the original programmer to solve it. The goal of Gadara is to allow anyone with our tool to solve the problem," Wang said.
Deadlock is becoming a more pressing concern as multicore chips grow in complexity and software performs an increasing number of tasks simultaneously. The bug shows up often in parallel programs that use shared data.
Gadara works by analyzing a program to find potential deadlocks, and then inserting control logic into the program. The control logic ensures that the program cannot deadlock.
Gadara uses a unique combination of discrete control theory and compiler technology, said Lafortune, whose primary work focuses on discrete control theory. The control theory provides the logic that allows Gadara to use feedback to prevent software deadlocks.
The compiler technology, which was developed by Scott Mahlke, a professor in the Department of Electrical Engineering and Computer Science, enables Gadara to operate on real-world applications. Compilers translate programs written in high-level programming languages in executable code.
University of Michigan
"This is a totally different approach to what people had done before for deadlock. Previously, engineers would try to identify potential deadlocks through testing or program analysis and then go back and rewrite the program. The bug fixes were manual, and not automatic. Gadara automates the process," said Stéphane Lafortune, a professor in the Department of Electrical Engineering and Computer Science and a Gadara developer.
Yin Wang, a doctoral student who works with Lafortune in the same department, will present a paper on Gadara Dec. 9 at the USENIX Symposium on Operating Systems Design and Implementation in San Diego.
"Every time you find a problem today you need the original programmer to solve it. The goal of Gadara is to allow anyone with our tool to solve the problem," Wang said.
Deadlock is becoming a more pressing concern as multicore chips grow in complexity and software performs an increasing number of tasks simultaneously. The bug shows up often in parallel programs that use shared data.
Gadara works by analyzing a program to find potential deadlocks, and then inserting control logic into the program. The control logic ensures that the program cannot deadlock.
Gadara uses a unique combination of discrete control theory and compiler technology, said Lafortune, whose primary work focuses on discrete control theory. The control theory provides the logic that allows Gadara to use feedback to prevent software deadlocks.
The compiler technology, which was developed by Scott Mahlke, a professor in the Department of Electrical Engineering and Computer Science, enables Gadara to operate on real-world applications. Compilers translate programs written in high-level programming languages in executable code.
University of Michigan
Control Theory Current Events and Control Theory News RSSResearchers achieve major breakthrough with water desalination system
Concern over access to clean water is no longer just an issue for the developing world, as California faces its worst drought in recorded history.
Grouping muscles to make controlling limbs easier
With more than 30 muscles in your arm, controlling movement -- whether it's grasping a glass or throwing a baseball -- is a complex task that potentially takes into account thousands of variables.
Mathematics reveals genetic pattern of tumor growth
Using mathematical theory, UC Irvine scientists have shed light on one of cancer's most troubling puzzles - how cancer cells can alter their own genetic makeup to accelerate tumor growth.
Small, self-controlled planes combine plant pathology and engineering
A Virginia Tech plant pathologist has developed autonomous unmanned aerial vehicles (UAVs) to detect airborne pathogens above agricultural fields.
Fighting sound with sound, new modeling technique could quiet aircraft
Newly published research by a Princeton engineer suggests that understanding how air travels across the sunroof of a car may one day make jet engines less noisy.
Invitation to the Media - Leading scientists describe their work at Royal Society seminar
Leading experts on cloning, the human genome, computer microprocessors, earthquakes and conservation will be describing their work at the Royal Society on 10 and 11 July. The annual Royal Society New Fellows Seminar will showcase the groundbreaking work carried out by new Fellows and Foreign Members elected this year. The speakers will include: Professor Stephen Furber, who helped design the world's leading embedded processor core for digital equipment; Professor Nicholas Hastie, who led the team that first demonstrated the tips of human chromosomes shorten with age; Dr Georgina Mace, who devised international standards for identifying plant and animal species that are at greatest risk of ex
More Control Theory Current Events and Control Theory News Articles
 |
Control Theory: A New Explanation of How We Control Our Lives by William Glasser (Author) |
 |
Optimal Control Theory: An Introduction by Donald E. Kirk (Author) Geared toward upper-level undergraduates, this text introduces three aspects of optimal control theory: dynamic programming, Pontryagin's minimum principle, and numerical techniques for trajectory optimization. Numerous problems, which introduce additional topics and illustrate basic concepts, appear throughout the text. Solution guide available upon request. 131 figures. 14 tables. 1970 edition. |
 |
Modern Control Theory (3rd Edition) by William L. Brogan (Author) M->CREATED |
 |
Schaum's Outline of Feedback and Control Systems (Schaum's) by Allen Stubberud (Author), Ivan Williams (Author), Joseph DiStefano (Author) If you want top grades and thorough understanding of feedback and control systems--both analog and digital--in less study time, this powerful study tool is the best tutor you can have! It takes you step-by-step through the subject and gives you accompanying problems with fully worked solutions--plus hundreds of additional problems with answers at the end of chapters, so you can measure your progress. You also get the benefit of clear, detailed illustrations. Famous for their clarity, wealth of illustrations and examples--and lack of tedious detail--Schaum's Outlines have sold more than 30 million copies worldwide. This guide will show you why! |
 |
Feedback Control Theory (Dover Books on Engineering) by John C. Doyle (Author), Bruce A. Francis (Author), Allen R. Tannenbaum (Author) An excellent introduction to feedback control system design, this book offers a theoretical approach that captures the essential issues and can be applied to a wide range of practical problems. Its explorations of recent developments in the field emphasize the relationship of new procedures to classical control theory. 1992 edition. |
 |
Optimal Control and Estimation (Dover Books on Advanced Mathematics) by Robert F. Stengel (Author) Graduate-level text provides introduction to optimal control theory for stochastic systems, emphasizing application of basic concepts to real problems. |
 |
A Mathematical Introduction to Control Theory (Series in Electrical and Computer Engineering) by Shlomo Engelberg (Author) Striking a careful balance between mathematical rigor and engineering-oriented applications, this textbook aims to maximize the readers' understanding of both the mathematical and engineering aspects of control theory. The bedrock elements of classical control theory are comprehensively covered: the Routh–Hurwitz theorem and applications, Nyquist diagrams, Bode plots, root locus plots, the design of controllers (phase-lag, phase-lead, lag-lead, and PID), and three further advanced topics: non-linear control, modern control and discrete-time control. A Mathematical Introduction to Control Theory will be an invaluable book for junior and senior level university students in engineering, particularly electrical engineering. Students with a good knowledge of algebra and complex... |
 |
Control System Design: An Introduction to State-Space Methods (Dover Books on Engineering) by Bernard Friedland (Author) Introduction to state-space methods covers feedback control; state-space representation of dynamic systems and dynamics of linear systems; frequency-domain analysis; controllability and observability; and shaping the dynamic response. Additional subjects encompass linear observers; compensator design by the separation principle; linear, quadratic optimum control; random processes; and Kalman filters. 1986 edition. |
 |
Introduction to Stochastic Control Theory by Karl J. Astrom (Author) This text for upper-level undergraduates and graduate students explores stochastic control theory in terms of analysis, parametric optimization, and optimal stochastic control. Limited to linear systems with quadratic criteria, it covers discrete time as well as continuous time systems. 1970 edition. |
 |
Modern Control Theory by Zdzislaw Bubnicki (Author) This compact and uniform textbook presents the contemporary state of the art of control theory and its applications. It introduces traditional problems useful in the automatic control of technical processes, as well as current issues, such as decision taking in conditions of uncertainty, use of artificial intelligence methods, or control of complex operations. The methods covered are introduced in a practice-oriented way that allows the reader to easily apply them for the determination of decision algorithms in computer control and management systems. This concise textbook is aimed at students of automatics, robotics, control engineering, and computer sciences. |
| © 2009 BrightSurf.com |