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13
The Stochastic Rendezvous Network model for the performance of synchronous clientserver like distributed software
 IEEE Transactions on Computers
, 1995
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LoPC: Modeling Contention in Parallel Algorithms
, 1997
"... Parallel algorithm designers need computational models that take first order system costs into account, but are also simple enough to use in practice. This paper introduces the LoPC model, which is inspired by the LogP model but accounts for contention for message processing resources in parallel al ..."
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Cited by 45 (8 self)
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Parallel algorithm designers need computational models that take first order system costs into account, but are also simple enough to use in practice. This paper introduces the LoPC model, which is inspired by the LogP model but accounts for contention for message processing resources in parallel algorithms on a multiprocessor or network of workstations. LoPC takes the , and parameters directly from the LogP model and uses them to predict the cost of contention, .
An Efficient Algorithm for the Exact Analysis of Multiclass Queueing Networks with Large Population Sizes
, 2006
"... We introduce an efficient algorithm for the exact analysis of closed multiclass productform queueing network models with large population sizes. We adopt a novel approach, based on linear systems of equations, which significantly reduces the cost of computing normalizing constants. With the propose ..."
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Cited by 14 (9 self)
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We introduce an efficient algorithm for the exact analysis of closed multiclass productform queueing network models with large population sizes. We adopt a novel approach, based on linear systems of equations, which significantly reduces the cost of computing normalizing constants. With the proposed algorithm, the analysis of a model with N circulating jobs of multiple classes requires essentially the solution of N linear systems with order independent of population sizes. A distinguishing feature of our approach is that we can immediately apply theorems, solution techniques, and decompositions for linear systems to queueing network analysis. Following this idea, we propose a block triangular form of the linear system that further reduces the requirements, in terms of both time and storage, of an exact analysis. An example illustrates the efficiency of the resulting algorithm in presence of large populations.
Physical Database Design Decision Algorithms and Concurrent Reorganization for Parallel Database Systems
, 1997
"... Stringent performance requirements in DB applications have led to the use of parallelism for database processing. To allow the database system to take advantage of the performance of parallel sharednothing systems, the physical DB design must be appropriate for the DB structure and the workload. We ..."
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Cited by 11 (1 self)
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Stringent performance requirements in DB applications have led to the use of parallelism for database processing. To allow the database system to take advantage of the performance of parallel sharednothing systems, the physical DB design must be appropriate for the DB structure and the workload. We develop decision algorithms that will select a good physical DB design both when the DB is first loaded into the system (static decision) and while the DB is being used by the workload (dynamic decision). Our decision algorithms take the database structure, workload, and system characteristics as inputs. The static (or initial) physical DB design decision algorithm involves: • selecting a partitioning attribute for each relation that determines how the relation is fragmented across the nodes (allowing for high I/O bandwidth); • selecting indexes on the relation attributes to allow faster accesses compared to sequential file scans; • selecting the attributes by which to cluster a relation in order to take advantage of the prefetching and caching involved in I/O access; • grouping of relations to allow DB operations (joins) on relation pairs to be executed locally
Performance Of Stochastic Rendezvous Networks With Priority Tasks
 Performace of Distributed and Parallel Systems
, 1988
"... Multitasking multiprocessor systems frequently use rendezvous for intertask communication, and Stochastic Rendezvous Networks are a form of performance model for such systems. Tasks are frequently given different priorities to adjust the system performance. This paper considers a preemptiveresume ..."
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Cited by 3 (3 self)
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Multitasking multiprocessor systems frequently use rendezvous for intertask communication, and Stochastic Rendezvous Networks are a form of performance model for such systems. Tasks are frequently given different priorities to adjust the system performance. This paper considers a preemptiveresume priority discipline for executing tasks sharing each processor. An iterative algorithm is proposed, based on the wellknown "MVA Priority Approximation". Throughput errors below 10% are found in many cases. The worst accuracy (as usual) is for lowpriority tasks on highlyutilized processors. 1 Introduction This paper considers the performance of multiprocessor multitasking systems with rendezvous, and the effect of priorities among tasks. Multitasking software applications are growing in importance, either for single processors, or for multiprocessors and networks. Performance models of these systems should take into account the software communications behavior, which introduces queuein...
ESTIMATING BOTTLENECKS OF VERY LARGE MODELS
"... Queueing theory has been extensively used since 70’s to carry out performance evaluations of complex computer systems. However, handling the complexity of modern computer networks with thousands of servers and millions of customers is still a challenge. Indeed, although the identification of product ..."
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Cited by 1 (0 self)
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Queueing theory has been extensively used since 70’s to carry out performance evaluations of complex computer systems. However, handling the complexity of modern computer networks with thousands of servers and millions of customers is still a challenge. Indeed, although the identification of productform queueing networks has promoted the development of computationally tractable exact solution techniques, the dimensionality of “very large ” models makes it difficult to meet the requirements of either exact and approximate algorithms. In this paper we focus on the bottleneck analysis as a technique that may provide answers to many capacity planning questions (e.g., “which is the maximum number of transactions per second the computer system is able to process? ” or “which is the minimum response time that can be achieved per transaction?”) for “very large ” computer installations with a limited complexity. The problem to be solved with this technique is the identification of the set of resources that may saturate among the thousands of components. We show some results concerning the application of the theory of convex polyhedra to bottleneck analysis that can sensibly reduce the complexity of the analysis. The connections between this technique and the behavior of closed and open models are also investigated. 1.
Performance Optimization of DistributedSy stem Models with Unreliable Servers
"... multipler technique ..."
Message Passing with Communication Structures
, 2006
"... Abstraction concepts based on process groups have largely dominated the design and implementation of communication patterns in message passing systems. Although such an approach seems pragmatic—given that participating processes form a ‘group’—in this dissertation, we discuss subtle issues that aff ..."
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Abstraction concepts based on process groups have largely dominated the design and implementation of communication patterns in message passing systems. Although such an approach seems pragmatic—given that participating processes form a ‘group’—in this dissertation, we discuss subtle issues that affect the qualitative and quantitative aspects of this approach. To address these issues, we introduce the concept of a ‘communication structure, ’ which defines a communication pattern as an implicit runtime composition of localised patterns, known as ‘roles. ’ During application development, communication structures are derived from the algorithm being implemented. These are then translated to an executable form by defining process specific data structures, known as ‘branching channels.’ The qualitative advantages of the communication structure approach are that the resulting programming model is nonambiguous, uniform, expressive, and extensible. To use a pattern is to access the corresponding branching channels; to define a new pattern is simply to combine appropriate roles. The communication
AN MVA APPROXIMATION FOR CONWIP PRIORITY MODELING
"... Constant workinprocess control (CONWIP) by product type is a strategy for improving the cycle time in multiple product factories. For realistic sized systems, a meanvalue analysis (MVA) approximation methodology yields quick and accurate results. A processing step modeling paradigm is developed f ..."
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Constant workinprocess control (CONWIP) by product type is a strategy for improving the cycle time in multiple product factories. For realistic sized systems, a meanvalue analysis (MVA) approximation methodology yields quick and accurate results. A processing step modeling paradigm is developed for the MVA methodology and applied to multipleproduct reentrantflow sequences. A variety of sequencing rules have been proposed in an attempt to improve the mean cycle times while maintaining the product throughput rates. A general priority scheme is developed for the MVA modeling approach which allows many of the sequencing rules to be implemented and evaluated under multiple product CONWIP control. Four priority schemes (FIFO, shortest expected processing time, shortest remaining processing time, and Wein’s workbalance) are illustrated for a data set from the literature. The best priority scheme, workbalance, obtained a 41 % mean processing time improvement over FIFO under push control and 37 % under CONWIP control. 1
An Efficient Algorithm for the Exact Analysis of Multiclass Queueing Networks with Large Population Sizes
"... We introduce an efficient algorithm for the exact analysis of closed multiclass productform queueing network models with large population sizes. We adopt a novel approach, based on linear systems of equations, which significantly reduces the cost of computing normalizing constants. With the propose ..."
Abstract
 Add to MetaCart
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We introduce an efficient algorithm for the exact analysis of closed multiclass productform queueing network models with large population sizes. We adopt a novel approach, based on linear systems of equations, which significantly reduces the cost of computing normalizing constants. With the proposed algorithm, the analysis of a model with N circulating jobs of multiple classes requires essentially the solution of N linear systems with order independent of population sizes. A distinguishing feature of our approach is that we can immediately apply theorems, solution techniques, and decompositions for linear systems to queueing network analysis. Following this idea, we propose a block triangular form of the linear system that further reduces the requirements, in terms of both time and storage, of an exact analysis. An example illustrates the efficiency of the resulting algorithm in presence of large populations.