10 research outputs found

    Environmental research infrastructures in the command and control anthropocene

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    Evaluation of hardware architectures for parallel execution of complex database operations

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    Abstract New database applications, primarily in the areas of engineering and knowledge-based systems, refer to complex objects (e.g. representation of a CAD workpiece or a VLSI chip) while performing their tasks. Retrieval, maintenance, and integrity checking of such complex objects consume substantial computing resources which were traditionally used by conventional database management systems in a sequential manner. Rigid performance goals dictated by interactive use and design environments imply new approaches to master the functionality of complex objects under satisfactory time restrictions. Because of the object granularity, the set orientation of the database interface, and the complicated algorithms for object handling, the exploitation of parallelism within such operations seems to be promising. Our main goal is the investigation and evaluation of different hardware architectures and their suitability to efficiently cope with workloads generated by database operations on complex objects. Apparently, employing just a number of processors is not a panacea for our database problem. The sheer horse power of machines does not help very much when data synchronization and event serialization requirements play a major role during object handling. What are the critical hardware architecture properties? How can the existing MIPS be best utilized for the data management functions when processing complex objects? To answer these questions and related issues, we discuss different kinds of architectures combining multiple processors: loosely-, tightly-, and closely-coupled. Furthermore, we consider parallelism at different levels of abstraction: the distribution of (sub-)queries or the decomposition of such queries and their concurrent evaluation at an inter-or intra-object level. Finally, we give some thoughts as to the problems of load control and transaction management

    Development of a parallel database environment

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    High performance disk array architectures.

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    Yeung Kai-hau, Alan.Thesis (Ph.D.)--Chinese University of Hong Kong, 1995.Includes bibliographical references.ACKNOWLEDGMENTS --- p.ivABSTRACT --- p.vChapter CHAPTER 1 --- Introduction --- p.1Chapter 1.1 --- The Information Age --- p.2Chapter 1.2 --- The Importance of Input/Output --- p.3Chapter 1.3 --- Redundant Arrays of Inexpensive Disks --- p.5Chapter 1.4 --- Outline of the Thesis --- p.7References --- p.8Chapter CHAPTER 2 --- Selective Broadcast Data Distribution Systems --- p.10Chapter 2.1 --- Introduction --- p.11Chapter 2.2 --- The Distributed Architecture --- p.12Chapter 2.3 --- Mean Block Acquisition Delay for Uniform Request Distribution --- p.16Chapter 2.4 --- Mean Block Acquisition Delay for General Request Distributions --- p.21Chapter 2.5 --- Optimal Choice of Block Sizes --- p.24Chapter 2.6 --- Chapter Summary --- p.25References --- p.26Chapter CHAPTER 3 --- Dynamic Multiple Parity Disk Arrays --- p.28Chapter 3.1 --- Introduction --- p.29Chapter 3.2 --- DMP Disk Array --- p.31Chapter 3.3 --- Average Delay --- p.37Chapter 3.4 --- Maximum Throughput --- p.47Chapter 3.5 --- Simulation with Precise Disk Model --- p.53Chapter 3.6 --- Chapter Summary --- p.58References --- p.59Appendix --- p.61Chapter CHAPTER 4 --- Dynamic Parity Logging Disk Arrays --- p.69Chapter 4.1 --- Introduction --- p.70Chapter 4.2 --- DPL Disk Array Architecture --- p.73Chapter 4.3 --- DPL Disk Array Operation --- p.79Chapter 4.4 --- Performance of DPL Disk Array --- p.83Chapter 4.5 --- Chapter Summary --- p.91References --- p.92Appendix --- p.94Chapter CHAPTER 5 --- Performance Analysis of Mirrored Disk Array --- p.101Chapter 5.1 --- Introduction --- p.102Chapter 5.2 --- Queueing Model --- p.103Chapter 5.3 --- Delay Analysis --- p.104Chapter 5.4 --- Numerical Examples and Simulation Results --- p.108References --- p.109Chapter CHAPTER 6 --- State Reduction in the Exact Analysis of Fork/Join Queues --- p.110Chapter 6.1 --- Introduction --- p.111Chapter 6.2 --- State Reduction For Closed Fork/Join Queueing Systems --- p.113Chapter 6.3 --- Extension To Open Fork/Join Queueing Systems --- p.118Chapter 6.4 --- Chapter Summary --- p.122References --- p.123Chapter CHAPTER 7 --- Conclusion and Future Research --- p.124Chapter 7.1 --- Summary --- p.125Chapter 7.2 --- Future Researches --- p.12

    Logging and Recovery in a Highly Concurrent Database

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    This report addresses the problem of fault tolerance to system failures for database systems that are to run on highly concurrent computers. It assumes that, in general, an application may have a wide distribution in the lifetimes of its transactions. Logging remains the method of choice for ensuring fault tolerance. Generational garbage collection techniques manage the limited disk space reserved for log information; this technique does not require periodic checkpoints and is well suited for applications with a broad range of transaction lifetimes. An arbitrarily large collection of parallel log streams provide the necessary disk bandwidth

    Hochleistungs-Transaktionssysteme: Konzepte und Entwicklungen moderner Datenbankarchitekturen

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    Das Buch richtet sich an Informatiker in Studium, Lehre, Forschung und Entwicklung, die an neueren Entwicklungen im Bereich von Transaktions- und Datenbanksystemen interessiert sind. Es entspricht einer überarbeiteten Version meiner im Februar 1993 vom Fachbereich Informatik der Universität Kaiserslautern angenommenen Habilitationsschrift. Neben der Präsentation neuer Forschungsergebnisse erfolgen eine breite Einführung in die Thematik sowie überblicksartige Behandlung verschiedener Realisierungsansätze, wobei auf eine möglichst allgemeinverständliche Darstellung Wert gelegt wurde. Der Text wurde durchgehend mit Marginalien versehen, welche den Aufbau der Kapitel zusätzlich verdeutlichen und eine schnelle Lokalisierung bestimmter Inhalte unterstützen sollen

    One Thousand Transactions per Second

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    Several companies intend to provide general-purpose processing systems capable of one thousand transactions This paper surveys the need for such systems and approaches being taken by three different groups. transaction per second. contrasts the This paper appears in the proceedings of IEEE COMPCON-85, held in San Francisco in February 1985.
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