ppxscal/embedding_network huggingface dataset:
The LRU-K page replacement algorithm for database disk buffering
Authors: Elizabeth J. O'Neil, Patrick E. O'Neil Gerhard Weikum
Venue: ACM SIGMOD Record (1993)

This paper introduces a new approach to database disk buffering, called the LRU-K method. The basic idea of LRU-K is to keep track of the times of the last K references to popular database pages, using this information to statistically estimate the interarrival times of references on a page by page basis. Although the LRU-K approach performs optimal statistical inference under relatively standard assumptions, it is fairly simple and incurs little bookkeeping overhead. As we demonstrate with simulation experiments, the LRU-K algorithm surpasses conventional buffering algorithms in discriminating between frequently and infrequently referenced pages. In fact, LRU-K can approach the behavior of buffering algorithms in which page sets with known access frequencies are manually assigned to different buffer pools of specifically tuned sizes. Unlike such customized buffering algorithms however, the LRU-K method is self-tuning, and does not rely on external hints about workload characteristics. Furthermore, the LRU-K algorithm adapts in real time to changing patterns of access.
CHAOSarc: kernel support for multiweight objects, invocations, and atomicity in real-time multiprocessor applications
Authors: Ahmed Gheith, Karsten Schwan
Venue: ACM Transactions on Computer Systems (TOCS) (1993)

CHAOSarc is an object-based multiprocessor operating system kernel that provides primitives with which programmers may easily construct objects of differing types and object invocations of differing semantics, targeting multiprocessor systems, and real-time applications. The CHAOSarc can guarantee desired performance and functionality levels of selected computations in real-time applications. Such guarantees can be made despite possible uncertainty in execution environments by allowing programs to adapt in performance and functionality to varying operating conditions. This paper reviews the primitives offered by CHAOSarc and demonstrates how the required elements of the CHAOSarc real-time kernel are constructed with those primitives.
Counting triangle crossings and halving planes
Authors: Tamal K. Dey, Herbert Edelsbrunner
Venue: Proceedings of the ninth annual symposium on Computational geometry (1993)

Every collection of t &ge; 2n2 triangles with a total of n vertices in R3 has Wt4n6 crossing pairs. This implies that one of their edges meets Wt3n6 of the triangles. From this it follows that n points in R3 have only O(n8/3) halving planes.
Non-Cayley Vertex-Transitive Graphs of Order Twice the Product of Two Odd Primes
Authors: Alice Ann Miller, Cheryl E. Praeger
Venue: Journal of Algebraic Combinatorics: An International Journal (1994)

For a positive integer n, does there exist a vertex-transitive graph &Gamma; on n vertices which is not a Cayley graph, or, equivalently, a graph &Gamma; on n vertices such that Aut &Gamma; is transitive on vertices but none of its subgroups are regular on vertices? Previous work (by Alspach and Parsons, Frucht, Graver and Watkins, Marusic and Scapellato, and McKay and the second author) has produced answers to this question if n is prime, or divisible by the square of some prime, or if n is the product of two distinct primes. In this paper we consider the simplest unresolved case for even integers, namely for integers of the form n &equals; 2pq, where 2 < q < p, and p and q are primes. We give a new construction of an infinite family of vertex-transitive graphs on 2pq vertices which are not Cayley graphs in the case where p &equiv; 1 (mod q). Further, if p &nequiv; 1 (mod q), p &equiv; q &equiv; 3(mod 4), and if every vertex-transitive graph of order pq is a Cayley graph, then it is shown that, either 2pq &equals; 66, or every vertex-transitive graph of order 2pq admitting a transitive imprimitive group of automorphisms is a Cayley graph.
Metamodeling: how, why and what?
Authors: Peter Kokol
Venue: ACM SIGSOFT Software Engineering Notes (1993)

The metamodeling is analyzed in the context of three crucial questions: How, why and What? This analysis showed that albeit the great advancement of process modeling in last years at least one important question still remains unsolved: How to design new process models? In this paper we introduce a metaparadigm as a possible solution to this question. Metaparadigm is a metadesign paradigm based on Checklands Soft System Methodology.
Secondary cache performance in RISC architecture
Authors: Benjamin J. Ewy, Joseph B. Evans
Venue: ACM SIGARCH Computer Architecture News (1993)

In this paper we report on a simulation study that examines a uniprocessor system with a three-level memory hierarchy. A simulation model of a single-cycle-per-instruction processor with a small on-chip cache was constructed and tested with various memory hierarchies. The simulation was intended to focus on meeting the demanding requirements of the latest RISC processors such as the MIPS R4000 and the DEC 21064. The simulator used allowed the authors to run traces of hundreds of millions of memory references per case. These long traces gave a more thorough and accurate picture of the memory demands of current processors. Data is presented enabling a designer to incorporate speed estimates based on implementation restrictions into the process of developing memory hierarchies.
A multitasking executive for operating systems courses
Authors: Christophe Haro, Christian Proust
Venue: ACM SIGOPS Operating Systems Review (1993)

This paper presents the design of a multitasking executive for a course on computer operating systems. The system described here allows us to illustrate some fundamental concepts of multiprocessing and to experiment parallel programming.The system built is a preempt multitask one, which implements semaphore as a synchronisation tool of concurrent programs. A software layer called SESSION MANAGER is built above the basic kernel which is hence isolated from user's processes.The whole system is thus conceived to be written and tested by students during their courses on basic systems.
Using state space reduction methods for deadlock analysis in Ada tasking
Authors: S. Duri, U. Buy, R. Devarapalli, S. M. Shatz
Venue: Proceedings of the 1993 ACM SIGSOFT international symposium on Software testing and analysis (1993)

Over the past few years, a number of research investigations have been initiated for static analysis of concurrent and distributed software. In this paper we report on experiments with various optimization techniques for reachability-based deadlock detection in Ada programs using Petri net models. Our experimental results show that various optimization techniques are mutually beneficial with respect to the effectiveness of the analysis.
Polymorphic strictness analysis using frontiers
Authors: Julian Seward
Venue: Proceedings of the 1993 ACM SIGPLAN symposium on Partial evaluation and semantics-based program manipulation (1993)

This paper shows how to implement sensible polymorphic strictness analysis using the Frontiers algorithm. A central notion is to only ever analyse each function once, at its simplest polymorphic instance. Subsequent non-base uses of functions are dealt with by generalising their simplest instance analyses. This generalisation is done using an algorithm developed by Baraki, based on embedding-closure pairs. Compared with an alternative approach of expanding the program out into a collection of monomorphic instances, this technique is hundreds of times faster for realistic programs. There are some approximations involved, but these do not seem to have a detrimental effect on the overall result. The overall effect of this technology is to considerably expand the range of programs for which the Frontiers algorithm gives useful results reasonably quickly.
Improving the software reusability in object-oriented programming
Authors: Jingwen Cheng
Venue: ACM SIGSOFT Software Engineering Notes (1993)

One of the promises which OOP (Object-Oriented Programming) holds is that it enhances software reusability. Indeed, software components designed in OOP is easier to be reused than those designed in conventional programming. But the state-of-the-art software reusability in most OOP environments is still very limited. This paper examines how OOP enhances software reusability, what are the limitations of software reuse in current state, and how to improve software reusability.
European Activities in Virtual Reality
Authors: José Encarnação, Martin Göbel, Lawrence Rosenblum
Venue: IEEE Computer Graphics and Applications (1994)

We survey European activities in virtual reality, with an emphasis on selected efforts in architecture and sound, telepresence, scientific visualization, simulation, software design, and entertainment. This article surveys European activities and funding for VR with two caveats: First, nearly a year separates writing and publication. For most scientific fields, this publication delay for survey material would be minimal: for virtual reality, significant changes might have since occurred in some programs. We took advantage of the revision period to upgrade our information and the references as much as possible. Second, some long standing, significant European efforts go unmentioned as outside the scope of our short survey or as duplicates of others included. Despite the limitations, this sampling of Europe's leading efforts collectively gives an accurate snapshot of current European activity.
A modern approach to grade preparation using Lotus 1-2-3
Authors: Arlene Podos, Marie Rummo
Venue: ACM SIGCUE Outlook (1994)

This article describes a technique that educators can use to simplify and automate the preparation of student grades. Instead of computing averages and determining letter grades individually for each student, the educator can use Lotus commands to calculate the averages and produce letter grades automatically for an entire class. Not only will this technique save considerable time and effort, it will also enable the instructor to produce more accurate and professional looking grading reports.
The globalized growth of the ACM scholastic programming contest (abstract)
Authors: William Poucher, Nikolay Ivanov, Sven Neirynck, Raewyn Boersen, C. J. Hwang
Venue: Proceedings of the 1993 ACM conference on Computer science (1993)

Although it originated at Texas A M University in the United States, the Scholastic Programming Contest has quickly evolved into an annual event attracting worldwide interest and participation. For the past several years, the Contest Steering Committee has been working to expand the contest's sphere of opportunity within the ACM community. The ultimate goal is to provide students of the computing sciences at every university in the world with a chance to participate in the contest. To accomplish this very ambitious task, a coordinated effort among ACM volunteers on a global scale must be established as part of the contest infrastructure. This panel session will trace the globalized growth of the contest and discuss many of the issues which must be addressed in order to make the ACM Scholastic Programming Contest sponsored by AT T EasyLink Services the premiere event of its kind in the world.
Algorithm 722: Functions to support the IEEE standard for binary floating-point arithmetic
Authors: W. J. Cody, Jerome T. Coonen
Venue: ACM Transactions on Mathematical Software (TOMS) (1993)

This paper describes C programs for the support functions copysign(x,y), logb(x), scalb(x,n), nextafter(x,y), finite(x), and isnan(x) recommended in the Appendix to the IEEE Standard for Binary Floating-Point Arithmetic. In the case of logb, the modified definition given in the later IEEE Standard for Radix-Independent Floating-Point Arithmetic is followed. These programs should run without modification on most systems conforming to the binary standard.
A transputer T9000 family based architecture for parallel database machines
Authors: Qiang Li, Naphtali Rishe
Venue: ACM SIGARCH Computer Architecture News (1993)

Parallel computing is a promising way to achieve high performance in a database system. The disk access speed has been a well known bottleneck for database machines, and the data intensive nature and the random communication patterns of databases make the interconnection network in a database machine difficult to design.This article describes the design of a highly parallel, high throughput database machine based on the new T9000 transputer family and a large number of relatively inexpensive disks. The database machine is designed to achieve a throughput of more than 10,000 elementary transactions per second and a total size in the range of terabytes. The Semantic Binary Database Model is employed by the system. Besides its logical aspects, this model's implementation facilitates the utilization of the parallel processing power and improves the reliability of the system.
Application of sampling methodologies to network traffic characterization
Authors: Kimberly C. Claffy, George C. Polyzos, Hans-Werner Braun
Venue: Conference proceedings on Communications architectures, protocols and applications (1993)

The relative performance of different data collection methods in the assessment of various traffic parameters is significant when the amount of data generated by a complete trace of a traffic interval is computationally overwhelming, and even capturing summary statistics for all traffic is impractical. This paper presents a study of the performance of various methods of sampling in answering questions related to wide area network traffic characterization. Using a packet trace from a network environment that aggregates traffic from a large number of sources, we simulate various sampling approaches, including time-driven and event-driven methods, with both random and deterministic selection patterns, at a variety of granularities. Using several metrics which indicate the similarity between two distributions, we then compare the sampled traces to the parent population. Our results revealed that the time-triggered techniques did not perform as well as the packet-triggered ones. Furthermore, the performance differences within each class (packet-based or time-based techniques) are small.
Interposition agents: transparently interposing user code at the system interface
Authors: Michael B. Jones
Venue: ACM SIGOPS Operating Systems Review (1993)

Many contemporary operating systems utilize a system call interface between the operating system and its clients. Increasing numbers of systems are providing low-level mechanisms for intercepting and handling system calls in user code. Nonetheless, they typically provide no higher-level tools or abstractions for effectively utilizing these mechanisms. Using them has typically required reimplementation of a substantial portion of the system interface from scratch, making the use of such facilities unwieldy at best.This paper presents a toolkit that substantially increases the ease of interposing user code between clients and instances of the system interface by allowing such code to be written in terms of the high-level objects provided by this interface, rather than in terms of the intercepted system calls themselves. This toolkit helps enable new interposition agents to be written, many of which would not otherwise have been attempted.This toolkit has also been used to construct several agents including: system call tracing tools, file reference tracing tools, and customizable filesystem views. Examples of other agents that could be built include: protected environments for running untrusted binaries, logical devices implemented entirely in user space, transparent data compression and/or encryption agents, transactional software environments, and emulators for other operating system environments.
Evolution of the PowerPC Architecture
Authors: Keith Diefendorff, Rich Oehler, Ron Hochsprung
Venue: IEEE Micro (1994)

The PowerPC is a new RISC architecture derived from IBM's POWER architecture. The changes made to POWER simplify implementations, increase clock rates, enable a higher degree of superscalar execution, extend the architecture to 64 bits, and add multiprocessor support. For compatibility with existing software, the developers retained POWER's basic instruction set, opcode assignments, and programming model.
A methodology for software cost estimation
Authors: Ali Arifoglu
Venue: ACM SIGSOFT Software Engineering Notes (1993)

Software Cost Estimation is an empirical process to be applied to find out basically the effort and development time requirements for the software product which is going to be developed. The process starts with the planning phase activities and refined throughout the development. It is very important for managing and scheduling the software project. Various cost estimation methods are available to be used for software development process. Depending on the size of the software, a macro (for the information systems requiring more than 30 man years to develop) or a micro cost model can be used for estimation. The paper discusses available work on the cost estimation methods and proposes a methodological view in cost estimation. Basically, the methodology involves; how to combine available cost estimation techniques to have better estimation and, how to apply the methodology through software development. In the application of the cost estimation techniques, SD (Structured Development/Design) methodology is assumed as applied during the development. Some of the observations in the experiments are also given in the paper.
A unified framework for conservative and optimistic distributed simulation
Authors: Vikas Jha, Rajive L. Bagrodia
Venue: ACM SIGSIM Simulation Digest (1994)

A great deal of research in the area of distributed discrete event simulation has focussed on evaluating the performance of variants of conservative and optimistic methods on different types of applications. Application characteristics like lookahead, communication patterns, etc. have been found to affect the suitability of a specific protocol to simulate a given model. For many systems, it may be the case that different subsystems possess contradictory characteristics such that whereas some subsystems may be simulated efficiently using a conservative protocol, others may be more amenable to optimistic methods. Furthermore, the suitability of a protocol for a given subsystem may change dynamically. We propose a parallel simulation protocol that allows different parts of a system to be simulated using different protocols, allowing these protocols to be switched dynamically. A proof of correctness is presented, along with some preliminary performance discussion.
Functions as passive constraints in LIFE
Authors: Hassan Aït-Kaci, Andreas Podelski
Venue: ACM Transactions on Programming Languages and Systems (TOPLAS) (1994)

LIFE is a programming language proposing to integrate logic programming, functional programming, and object-oriented programming. It replaces first-order terms with &psgr;-terms, data structures that allow computing with partial information. These are approximation structures denoting sets of values. LIFE further enriches the expressiveness of &psgr;-terms with functional dependency constraints. We must explain the meaning and use of functions in LIFE declaratively, as solving partial information constraints. These constraints do not attempt to generate their solutions but behave as demons filtering out anything else. In this manner, LIFE functions act as declarative coroutines. We need to show that the &psgr;-term's approximation semantics is congruent with an operational semantics viewing functional reduction as an effective enforcing of passive constraints. In this article, we develop a general formal framework for entailment and disentailment of constraints based on a technique called relative simplification. We study its operational and semantical properties, and we use it to account for functional application over &psgr;-terms in LIFE.
Typesetting APL with LATEX: the APL front end APL2TEX
Authors: Andreas Geyer-Schulz, Josef Matulka, Gustaf Neumann
Venue: ACM SIGAPL APL Quote Quad (1993)

In this paper we present an APL publishing system for LATEX which supports typesetting of APL publications and documents in a mixed hardware, multiple vendor APL environment. It requires minimal maintenance and is in the public domain. The system has two components, the LATEX document style option apl.sty and the APL2TEX front end. apl.sty currently provides the full symbol sets of the APL dialects APL2/370, APL2/PC, Dyalog APL, I---APL, Sharp APL, and APL.68000 Levels I and II. All APL symbols are constructed with the symbols of the standard LATEX font family. No special fonts are needed. The APL2TEX front end is a workspace containing a preprocessor for converting APL objects to LATEX logical document elements. APL2TEX is currently available for APL2/370, APL2/PC, Dyalog APL and APL.68000 Levels I and II.
An instant and accurate size estimation method for joins and selections in a retrieval-intensive environment
Authors: Wei Sun, Yibei Ling, Naphtali Rishe, Yi Deng
Venue: ACM SIGMOD Record (1993)

This paper proposes a novel strategy for estimating the size of the resulting relation after an equi-join and selection using a regression model. An approximating series representing the underlying data distribution and dependency is derived from the actual data. The proposed method provides an instant and accurate size estimation by performing an evaluation of the series, with no run-time overheads in page faults and space, and with negligible CPU overhead. In contrast, the popular sampling methods incur run-time overheads in page faults (for sampling), CPU time and space. These overheads of sampling methods increase the response time of processing a query. The results of a comprehensive experimental study are also reported, which demonstrate that the estimation accuracy by the proposed method is comparable with that of the sampling methods which are believed to provide the most accurate estimation. The proposed method seems ideal for retrieval-intensive database and information systems. Since the overheads involved in deriving the approximating series are fairly moderate, we believe that this method is also an extremely competent method when moderate or periodical updates are present.
Dynamic graph drawing (abstract)
Authors: Robert F. Cohen
Venue: ACM SIGACT News (1993)

An automatic layout facility is a tool that receives as input a graph-like structure and is able to produce a diagram that nicely represents such a structure. Because of the increasing number of systems that manage diagrams, automatic layout facilities and algorithms for graphs layout have been extensively studied in the last years. We present a new approach in designing an automatic layout facility. Our approach is based on a modular management of a collection of algorithms and on a tool that is able to automatically select the best algorithm for a given application. Such approach has been used for devising the automatic layout facility of Diagram Server, a network server that offers to its clients several facilities for managing diagrams. (Joint work with P. Bertolazzi and G. Di Battista.)
Why users cannot &ldquo;get what they want&rdquo;
Authors: Ray J. Paul
Venue: ACM SIGOIS Bulletin (1993)

The notion that users can 'get what they want' has caused a planning blight in information systems development, with the resultant plethora of information slums that require extensive and expensive maintenance. This paper will outline why the concept of 'user requirements' has led to a variety of false paradigms for information systems development, with the consequent creation of dead systems that are supposed to work in a living organisation. It is postulated that what is required is an architecture for information systems that is designed for breathing, for adapting to inevitable and unknown change. Such an architecture has less to do with 'what is wanted', and more to do with the creation of a living space within the information system that enables the system to live.