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A Unified Approach for Specifying Measures of Performance, Dependability, and Performability
, 1991
"... Methods for evaluating system performance, dependability, and performability are becoming increasingly more important, particularly in the case of critical applications. Central to the evaluation process is the definition of specific measures of system behavior that are of interest to a user. This p ..."
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Cited by 59 (7 self)
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Methods for evaluating system performance, dependability, and performability are becoming increasingly more important, particularly in the case of critical applications. Central to the evaluation process is the definition of specific measures of system behavior that are of interest to a user. This paper presents a unified approach to the specification of measures of performance, dependability, and performability. The unification is achieved by 1) using a model class well suited for representation of all three aspects of system behavior, and 2) system behavior. The resulting approach permits the specification of many nontraditional as well as traditional measures of system performance, dependability, and performability in a unified manner. Example instantiations of variables within this class are given and their relationships to variables used in traditional performance and dependability evaluations are illustrated.
Stochastic petri nets: An elementary introduction
 In Advances in Petri Nets
, 1989
"... ABSTRACT Petri nets in which random firing delays are associated with transitions whose ..."
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Cited by 58 (0 self)
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ABSTRACT Petri nets in which random firing delays are associated with transitions whose
Aperiodic Task Scheduling for RealTime Systems
, 1990
"... This thesis develops the Sporadic Server (SS) algorithm for scheduling aperiodic tasks in realtime systems. The SS algorithm is an extension of the rate monotonic algorithm which was designed to schedule periodic tasks. This thesis demonstrates that the SS algorithm is able to guarantee deadlines f ..."
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Cited by 46 (0 self)
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This thesis develops the Sporadic Server (SS) algorithm for scheduling aperiodic tasks in realtime systems. The SS algorithm is an extension of the rate monotonic algorithm which was designed to schedule periodic tasks. This thesis demonstrates that the SS algorithm is able to guarantee deadlines for harddeadline aperiodic tasks and provide good responsiveness for softdeadline aperiodic tasks while avoiding the schedulability penalty and implementation complexity of previous aperiodic service algorithms. It is also proven that the aperiodic servers created by the SS algorithm can be treated as equivalentlysized periodic tasks when assessing schedulability. This allows all the scheduling theories developed for the rate monotonic algorithm to be used to schedule aperiodic tasks. For scheduling aperiodic and periodic tasks that share data, this thesis defines the interactions and schedulability impact of using the SS algorithm with the priority inheritance protocols. For scheduling ha...
Analysis of Striping Techniques in Robotic Storage Libraries
 In Proceedings of the Fourteenth IEEE Symposium on Mass Storage Systems
, 1995
"... In recent years advances in computational speed have been the main focus of research and development in high performance computing. In comparison, the improvement in I/O performance has been modest. Faster processing speeds have created a need for faster I/O as well as for storage and retrieval of v ..."
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Cited by 43 (2 self)
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In recent years advances in computational speed have been the main focus of research and development in high performance computing. In comparison, the improvement in I/O performance has been modest. Faster processing speeds have created a need for faster I/O as well as for storage and retrieval of vast amounts of data. The technology needed to develop these mass storage systems exists today. Robotic storage libraries are vital components of such systems; however, they normally exhibit high latency and long transmission times. In this paper we analyze the performance of robotic storage libraries and study striping as a technique for improving response time. We show that striping, which improves the effective bandwidth, introduces overhead into the usage of the library's resources, and hence conditions under which it is advantageous are highly dependent on the system's workload. This work was partially done while the author was a summer student at the Lawrence Livermore National Labora...
Timedivision optical communications in multiprocessor arrays
 IEEE Transactions on Computers
, 1993
"... ..."
Anagnostakis. Puppetnets: Misusing web browsers as a distributed attack infrastructure (extended version
, 2006
"... Most of the recent work on Web security focuses on preventing attacks that directly harm the browser’s host machine and user. In this paper we attempt to quantify the threat of browsers being indirectly misused for attacking third parties. Specifically, we look at how the existing Web infrastructure ..."
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Cited by 29 (2 self)
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Most of the recent work on Web security focuses on preventing attacks that directly harm the browser’s host machine and user. In this paper we attempt to quantify the threat of browsers being indirectly misused for attacking third parties. Specifically, we look at how the existing Web infrastructure (e.g., the languages, protocols, and security policies) can be exploited by malicious Web sites to remotely instruct browsers to orchestrate actions including denial of service attacks, worm propagation and reconnaissance scans. We show that, depending mostly on the popularity of a malicious Web site and user browsing patterns, attackers are able to create powerful botnetlike infrastructures that can cause significant damage. We explore the effectiveness of countermeasures including anomaly detection and more finegrained browser security policies.
Flow Theory
, 1997
"... We develop a simple theory of flows to study the flow of data in realtime computing networks. Flow Theory is based on discrete and nondeterministic mathematics, rather than the customary continuous or probabilistic mathematics. The theory features two types of flows: smooth and uniform, and eight ..."
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Cited by 25 (12 self)
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We develop a simple theory of flows to study the flow of data in realtime computing networks. Flow Theory is based on discrete and nondeterministic mathematics, rather than the customary continuous or probabilistic mathematics. The theory features two types of flows: smooth and uniform, and eight types of flow operators. We prove that, if the input flow to any of these operators is smooth or uniform, then both the internal buffer and delay of that operator are bounded. Linear networks of flow operators are introduced, and their internal buffers and delays are derived from the internal buffers and delays of their constituent operators. We extend Flow Theory so that it can be used in analyzing cyclic networks and networks of multiflows. Since many ratereservation protocols can be represented as linear networks of flow operators, we use Flow Theory to prove that a number of these protocols (StopandGo, Hierarchical RoundRobin, Weighted Fair Queueing, SelfClocking Fair Queueing, and Virtual Clock) require bounded buffering and introduce bounded delay.
Temporal Query Processing and Optimization in Multiprocessor Database Machines
, 1992
"... In this paper, we discuss issues involving temporal data fragmentation, temporal query processing, and query optimization in multiprocessor database machines. We propose parallel processing strategies, which are based on partitioning of temporal relations on timestamp values, for multiway joins (e. ..."
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Cited by 21 (0 self)
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In this paper, we discuss issues involving temporal data fragmentation, temporal query processing, and query optimization in multiprocessor database machines. We propose parallel processing strategies, which are based on partitioning of temporal relations on timestamp values, for multiway joins (e.g., complex temporal pattern queries) and optimization alternatives. We analyze the proposed schemes quantitatively, and show their advantages in computing complex temporal joins.
On Performance Prediction of Parallel Computations with Precedent Constraints
, 1994
"... Performance analysis of concurrent executions in parallel systems has been recognized as a challenging problem. The aim of this research is to study approximate but ecient solution techniques for this problem. We model the structure of a parallel machine and the structure of the jobs executing on ..."
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Cited by 15 (0 self)
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Performance analysis of concurrent executions in parallel systems has been recognized as a challenging problem. The aim of this research is to study approximate but ecient solution techniques for this problem. We model the structure of a parallel machine and the structure of the jobs executing on such a system. We investigate rich classes of jobs, which can be expressed by series, paralleland, parallelor, and probabilisticfork. We propose an efficient performance prediction method for these classes of jobs running on a parallel environment which is modeled by a standard queueing network model. The proposed prediction method is computationally efficient, it has polynomial complexity in both time and space. The time complexity is O(C²N²K) and the space complexity is O(C²N²K), where C is the number of job classes in the system, the number of tasks in each job class is O(N), and K is the number of service centers in the queueing model. The accuracy of the approxi...