ppxscal/embedding_network huggingface dataset:
Processor-pool-based scheduling for large-scale NUMA multiprocessors
Authors: Songnian Zhou, Timothy Brecht
Venue: ACM SIGMETRICS Performance Evaluation Review (1991)

Large-scale Non-Uniform Memory Access (NUMA) multiprocessors are gaining increased attention due to their potential for achieving high performance through the replication of relatively simple components. Because of the complexity of such systems, scheduling algorithms for parallel applications are crucial in realizing the performance potential of these systems. In particular, scheduling methods must consider the scale of the system, with the increased likelihood of creating bottlenecks, along with the NUMA characteristics of the system, and the benefits to be gained by placing threads close to their code and data.We propose a class of scheduling algorithms based on processor pools. A processor pool is a software construct for organizing and managing a large number of processors by dividing them into groups called pools. The parallel threads of a job are run in a single processor pool, unless there are performance advantages for a job to span multiple pools. Several jobs may share one pool. Our simulation experiments show that processor pool-based scheduling may effectively reduce the average job response time. The performance improvements attained by using processor pools increase with the average parallelism of the jobs, the load level of the system, the differentials in memory access costs, and the likelihood of having system bottlenecks. As the system size increasesr, while maintaining the workload composition and intensity, we observed that processor pools can be used to provide significant performance improvements. We therefore conclude that processor pool-based scheduling may be an effective and efficient technique for scalable systems.
A Very High Speed Architecture for Simulated Annealing
Authors: David Abramson
Venue: Computer (1992)

A class of scheduling problems that can be modeled by using very simple cost measures, namely, counting costs and distance-measure costs, is presented. These measures can be incorporated into a simulated annealing algorithm, providing a robust system for solving such scheduling problems. A special-purpose computer architecture that supports the simulated annealing of such problems is described. This architecture provides speeds greatly surpassing those of conventional workstations and supercomputers using the same algorithm.
On understanding type declarations in C
Authors: R. P. Mody
Venue: ACM SIGPLAN Notices (1992)

A small set of rules is given to produce and decipher complicated types in C.
On Self-Routing in Benes and Shuffle-Exchange Networks
Authors: C. S. Raghavendra, Rajendra V. Boppana
Venue: IEEE Transactions on Computers (1991)

The authors present self-routing algorithms for realizing the class of linear permutations in various multistage networks such as Benes and 2n-stage shuffle-exchange. Linear permutations are useful in providing fast access of data arrays. In the first half of the network, switches are set by comparing the destination tags at their inputs, and, in the second half, switches are set using the Omega self-routing algorithm. It is shown that the comparison operations can be implemented in bit-serial networks without loss of time. In contrast, with the well-known Benes network self-routing algorithm of D. Nassimi and S. Sahni (1981), switches are set by giving priority to the destination tag at the upper input to them. The algorithms presented are useful in providing fast access of various data patterns using interconnection networks cheaper than crossbars.
Directory of educational discounts, donations, and grants
Authors: Hubert Callihan
Venue: ACM SIGGRAPH Computer Graphics (1992)

The information included here was compiled using responses from 36 hardware and software vendors who were among 189 exhibitors attending the 1991 SIGGRAPH Conference in Las Vegas. Product descriptions and other details vary, but in most cases, provide enough information for educators to inquire further about opportunities to obtain products at a discount, as a donation, or possibly as a grant in connection with academic research. Companies responding that have neither educational discount, donation nor grant programs are not listed. SIGGRAPH encourages its conference exhibitors to submit a Directory listing for the benefit of educators. Listing a company or product in the Directory does not imply endorsement by either ACM or SIGGRAPH. Neither does it imply that the listing reflects the most recent policy of any vendor in effect after November 15, 1991. Educators should confirm any discount opportunities directly with the vendor.
Absolute Minimization of Completely Specified Switching Functions
Authors: Sung Je Hong, Saburo Muroga
Venue: IEEE Transactions on Computers (1991)

For the automated design of PLAs (programmable logic arrays) with a minimum size, computationally efficient procedures are needed that can minimize functions of a large number of variables. For such minimization procedures, excessively long processing time and an excessively large memory requirement are major problems to overcome. An absolute minimization procedure is presented for standard PLAs with reduced computation time and memory space. The improvement achieved by this procedure, which is based on the decomposition of ratio sets, is mainly due to the detection of all essential prime implicants during the derivation of inclusion functions and to the merger of two procedures previously published by R.B. Cutler and S. Muroga (1987) into one efficient procedure.
The first annual large dense linear system survey
Authors: Alan Edelman
Venue: ACM SIGNUM Newsletter (1991)

In the March 24, 1991 issue of NA Digest, I submitted a questionnaire asking who was solving large dense linear systems of equations. Based on the responses, nearly all large dense linear systems today arise from either the benchmarking of supercomputers or applications involving the influence of a two dimensional boundary on three dimensional space. Not surprisingly, the area of computational aerodynamics or aero-electromechanics represents an important commercial application requiring the solution of such systems. The largest unstructured matrix that has been factored using Gaussian Elimination was a complex matrix of size 55,296. The largest dense matrix solved on a Sun using an iterative method was a real matrix of size 20,000. It is unclear at this time whether dense methods are truly needed at all for huge matrices. It is intended to survey users every year with the hope of including more applications as I am made aware of them.
The role of software configuration management in a measurement-based software engineering program
Authors: Kristopher G. Sprague
Venue: ACM SIGSOFT Software Engineering Notes (1991)

The role of Software Configuration Management has rapidly expanded and grown in importance over the last few years for a number of reasons. This paper presents an overview of the significant changes that are occurring in the Software Configuration Management discipline with respect to its role in a measurement-based software engineering program. It identifies the changes, provides an overview of the SCM functions, proposes a process, and discusses directions for future research and development.
Intelligent I/O rule-based input/output processing for operating systems
Authors: Garbriel Broner, Patrick Powell
Venue: ACM SIGOPS Operating Systems Review (1991)

IntelligentI/O is a rule based general model for performing "intelligent" processing of Input/Output operations in an Operating System. In a new interface layer between the applications and the kernel I/O functions, rules determine actions to be performed at I/O time which in turn invoke programs in user space. IntelligentI/O permits complete implementation in user space applications that would normally require ad-hoc kernel modifications such as a Network File System. It also serves to implement features that would normally have to be embedded in an application, such as Automatic Format Conversion or Revision Tracking. We later present SuperFile, a simple yet powerful existing implementation of the IntelligentI/O model, together with a number of applications developed using SuperFile.
An Empirical Comparison of Software Fault Tolerance and Fault Elimination
Authors: Timothy J. Shimeall, Nancy G. Leveson
Venue: IEEE Transactions on Software Engineering (1991)

The authors compared two major approaches to the improvement of software-software fault elimination and software fault tolerance-by examination of the fault detection (and tolerance, where applicable) of five techniques: run-time assertions, multiversion voting, functional testing augmented by structural testing, code reading by stepwise abstraction, and static data-flow analysis. The focus was on characterizing the sets of faults detected by the techniques and on characterizing the relationships between these sets of faults. Two categories of questions were investigated: (1) comparison between fault elimination and fault tolerance techniques and (2) comparisons among various testing techniques. The results provide information useful for making decisions about the allocation of project resources, show strengths and weaknesses of the techniques studies, and indicate directions for future research.
On recursive calculation of the generalized inverse of a matrix
Authors: Saleem Mohideen, Vladimir Cherkassky
Venue: ACM Transactions on Mathematical Software (TOMS) (1991)

The generalized inverse of a matrix is an extension of the ordinary square matrix inverse which applies to any matrix (e.g., singular, rectangular). The generalized inverse has numerous important applications such as regression analysis, filtering, optimization and, more recently, linear associative memories. In this latter application known as Distributed Associative Memory, stimulus vectors are associated with response vectors and the result of many associations is spread over the entire memory matrix, which is calculated as the generalized inverse. Addition/deletion of new associations requires recalculation of the generalized inverse, which becomes computationally costly for large systems. A better solution is to calculate the generalized inverse recursively. The proposed algorithm is a modification of the well known algorithm due to Rust et al. [2], originally introduced for nonrecursive computation. We compare our algorithm with Greville's recursive algorithm and conclude that our algorithm provides better numerical stability at the expense of little extra computation time and additional storage.
Generalization of Queueing Network Product Form Solutions to Stochastic Petri Nets
Authors: Gerard Florin, Stéphane Natkin
Venue: IEEE Transactions on Software Engineering (1991)

A new solution is given for the steady-state probability computation of closed synchronized queuing networks. A closed synchronized queuing network is a particular Markov stochastic Petri net (a bounded and monovaluated Petri net with a strongly connected reachability graph and constant firing rates independent of markings). It is shown that the steady-state probability distribution can be expressed using matrix products. The results generalize the Gordon-Newell theorem. The solution is similar to the Gordon-Newell product form using matrix and vectors instead of scalars. A prototype solver developed from this result is presented.
A testbed for characterizing dynamic response of virtual environment spatial sensors
Authors: Bernard D. Adelstein, Eric R. Johnston, Stephen R. Ellis
Venue: Proceedings of the 5th annual ACM symposium on User interface software and technology (1992)

This paper describes a testbed and method for characterizing the dynamic response of the type of spatial displacement transducers commonly used in virtual environment (VE) applications. The testbed consists of a motorized rotary swing arm that imparts known displacement inputs to the VE sensor. The experimental method involves a series of tests in which the sensor is displaced back and forth at a number of controlled frequencies that span the bandwidth of volitional human movement. During the tests, actual swing arm angle and reported VE sensor displacements are collected and time stamped. Because of the time stamping technique, the response time of the sensor can be measured directly, independent of latencies in data transmission from the sensor unit and any processing by the interface applications running on the host computer. Analysis of these experimental results allows sensor time delay and gain characteristics to be determined as a function of input frequency. Results from tests of several differnt VE spatial sensors (Ascension, Logitech, and Polhemus) are presented here to demonstrate use of the testbed and method.
Modeling Security-Relevant Data Semantics
Authors: Gary W. Smith
Venue: IEEE Transactions on Software Engineering (1991)

The use of an extended data model which represents both integrity and secrecy aspects of data is demonstrated. This Semantic Data Model for Security (SDMS) provides a technique that assists domain experts, security officers, and database designers in first understanding their security requirements, and then translating them into a good database design. Identifying security requirements at this semantic level provides the basis for analyzing the security requirements and the database design for inference and signaling vulnerabilities. Another contribution is a comprehensive taxonomy of security-relevant data semantics that must be captured and understood to implement a multilevel secure automated information system.
Another C Threads library
Authors: G. Cattaneo, G. Di Giore, M. Ruotolo
Venue: ACM SIGPLAN Notices (1992)

In this paper we present the main results achieved with the implementation of an efficient multithread library, hereinafter called DIA_Thread library, built on the top of a shared memory symmetric multiprocessor environment. The idea which led us to this project was the lack of a minimal common layer which, as far the multitasking concerns, should help us to make our applications portable among different architectures and/or operating systems. In fact, there are more and more multiprocessor machines available but it is still difficult to exploit the inherent parallelism of the underlying hardware inside a single user application because the available tools are often different in performance and semantics.This package is intendend to be portable. It consists of less than two thousands lines of C code and only a few lines of assembly code. Moreover bif effort was spent to design the main structures in order to have a package absolutely architecture independent, that is, the dependencies on the host operating system were minimized and no assumption was made on the processor configuration, both on their total number and their basic interprocess communication support.The DIA_Thread library basically provides few functions to activate and manage multiple flows of control with a little extra overhead. The useer application may be split in a virtually unlimited number of threads which will carry on their own task communicating each other by means of common memory areas protected by semaphores.
obTIOS: a CAx-framework service for building concurrent engineering environments
Authors: Remco Quester
Venue: ACM SIGSOFT Software Engineering Notes (1992)

An open integrated CAx-framework supplies services to build derived CAx-environments (e.g. for concurrent Engineering (CE), VLSI-design, Software Engineering, etc.) with specialized, integrated in-house or foreign tools. Such integrated tool uses services of the CAx-framework and cooperates with other integrated tools to achieve a common engineering objective like the simulation of a VLSI-circuit. In most CAx-frameworks the integrated tools cooperate indirectly using CAx-framework services like Data Handling or Inter-Tool Communication (ITC). With obTIOS a high-level approach to control cooperation of integrated tools within a Computer Aided Concurrent Engineering (CACE) environment is introduced. The tools of a CACE-environment are grouped to domains which represent the most coarse, mutually independent, structural unit within the CACE-environment. The way in which the tools of a domain cooperate is described by Encapsulated Composed Activities (ECA). An ECA represents a template of control regarding cooperation-in-the-large and cooperation-in-the-small of tools.
Static Rate-Optimal Scheduling of Iterative Data-Flow Programs Via Optimum Unfolding
Authors: Keshab K. Parhi, David G. Messerschmitt
Venue: IEEE Transactions on Computers (1991)

Rate-optimal compile-time multiprocessor scheduling of iterative dataflow programs suitable for real-time signal processing applications is discussed. It is shown that recursions or loops in the programs lead to an inherent lower bound on the achievable iteration period, referred to as the iteration bound. A multiprocessor schedule is rate-optimal if the iteration period equals the iteration bound. Systematic unfolding of iterative dataflow programs is proposed, and properties of unfolded dataflow programs are studied. Unfolding increases the number of tasks in a program, unravels the hidden concurrently in iterative dataflow programs, and can reduce the iteration period. A special class of iterative dataflow programs, referred to as perfect-rate programs, is introduced. Each loop in these programs has a single register. Perfect-rate programs can always be scheduled rate optimally (requiring no retiming or unfolding transformation). It is also shown that unfolding any program by an optimum unfolding factor transforms any arbitrary program to an equivalent perfect-rate program, which can then be scheduled rate optimally. This optimum unfolding factor for any arbitrary program is the least common multiple of the number of registers (or delays) in all loops and is independent of the node execution times. An upper bound on the number of processors for rate-optimal scheduling is given.
On taxonomic reasoning in conceptual design
Authors: Sonia Bergamaschi, Claudio Sartori
Venue: ACM Transactions on Database Systems (TODS) (1992)

Taxonomic reasoning is a typical task performed by many AI knowledge representation systems. In this paper, the effectiveness of taxonomic reasoning techniques as an active support to knowledge acquisition and conceptual schema design is shown. The idea developed is that by extending conceptual models with defined concepts and giving them rigorous logic semantics, it is possible to infer isa relationships between concepts on the basis of their descriptions. From a theoretical point of view, this approach makes it possible to give a formal definition for consistency and minimality of a conceptual schema. From a pragmatic point of view it is possible to develop an active environment that allows automatic classification of a new concept in the right position of a given taxonomy, ensuring the consistency and minimality of a conceptual schema. A formalism that includes the data semantics of models giving prominence to type constructors (E/R, TAXIS, GALILEO) and algorithms for taxonomic inferences are presented: their soundness, completeness, and tractability properties are proved. Finally, an extended formalism and taxonomic inference algorithms for models giving prominence to attributes (FDM, IFO) are given.
The modelling and retrieval of documents using index expressions
Authors: P. D. Bruza, T. P. van der Weide
Venue: ACM SIGIR Forum (1991)

In this paper we introduce Index Expressions as a means for modelling document content. From an index expression the the Power Index Expression can be derived, which is a powerful instrument for information retrieval. We describe the characterization of documents in the style of formal logic. The content of a document is then modelled by a set of axioms, of which the document is a model. Relating a document to a query is done by proving the query from the axioms of that document. We introduce three rules of inference. If such a proof is not possible, the relevance of the document for the query is derived by plausible deduction. We introduce two inference rules for plausible deduction.
Comparative Analysis of Backpropagation and the Extended Kalman Filter for Training Multilayer Perceptrons
Authors: Dennis W. Ruck, Steven K. Rogers, Matthew Kabrisky, Peter S. Maybeck, Mark E. Oxley
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1992)

The relationship between backpropagation and extended Kalman filtering for training multilayer perceptrons is examined. These two techniques are compared theoretically and empirically using sensor imagery. Backpropagation is a technique from neural networks for assigning weights in a multilayer perceptron. An extended Kalman filter can also be used for this purpose. A brief review of the multilayer perceptron and these two training methods is provided. Then, it is shown that backpropagation is a degenerate form of the extended Kalman filter. The training rules are compared in two examples: an image classification problem using laser radar Doppler imagery and a target detection problem using absolute range images. In both examples, the backpropagation training algorithm is shown to be three orders of magnitude less costly than the extended Kalman filter algorithm in terms of a number of floating-point operations.
Cluster-based file replication in large-scale distributed systems
Authors: Harjinder S. Sandhu, Songnian Zhou
Venue: Proceedings of the 1992 ACM SIGMETRICS joint international conference on Measurement and modeling of computer systems (1992)

The increasing need for data sharing in large-scale distributed systems may place a heavy burden on critical resources such as file servers and networks. Our examination of the workload in one large commercial engineering environment shows that wide-spread sharing of unstable files among tens to hundreds of users is common. Traditional client-based file cacheing techniques are not scalable in such environments. We propose Frolic, a scheme for cluster-based file replication in large-scale distributed file systems. A cluster is a group of workstations and one or more file servers on a local area network. Large distributed systems may have tens or hundreds of clusters connected by a backbone network. By dynamically creating and maintaining replicas of shared files on the file servers in the clusters using those files, we effectively reduce reliance on central servers supporting such files, as well as reduce the distances between the accessing sites and data. We propose and study algorithms for the two main issues in Frolic, 1) locating a valid file replica, and 2) maintaining consistency among replicas. Our simulation experiments using a statistical workload model based upon measurement data and real workload characteristics show that cluster-based file replication can significantly reduce file access delays and server and backbone network utilizations in large-scale distributed systems over a wide range of workload conditions. The workload characteristics most critical to replication performance are: the size of shared files, the number of clusters that modify a file, and the number of consecutive accesses to files from a particular cluster.