2562587
Creating a Robust Desktop Grid using Peer-to-Peer Services
The goal of the work described in this paper is to design and build a scalable infrastructure for executing grid applications on a widely distributed set of resources. Such grid infrastructure must be decentralized, robust, highly available, and scalable, while efficiently mapping application instances to available resources in the system. However, current desktop grid computing platforms are typically based on a client-server architecture, which has inherent shortcomings with respect to robustness, reliability and scalability. Fortunately, these problems can be addressed through the capabilities promised by new techniques and approaches in peer-to-peer (P2P) systems. By employing P2P services, our system allows users to submit jobs to be run in the system and to run jobs submitted by other users on any resources available in the system, essentially allowing a group of users to form an ad-hoc set of shared resources. The initial target application areas for the desktop grid system are in astronomy and space science simulation and data analysis.
2757542
Comparing the performance of high-level middleware systems in shared and distributed memory parallel environments
The utilization of toolkits for writing parallel and/or distributed applications has been shown to greatly enhance developer's productivity. Such an approach hides many of the complexities associated with writing these applications, rather than relying solely on programming language aids and parallel library support, such as MPI or PVM. In this work, we evaluate three different middleware systems that have been used to implement a computation and I/O-intensive data analysis application from the domain of computer vision. This study shows the benefits and overheads associated with each of the middleware systems, in different homogeneous computational environments and with different workloads. Our results lead the way toward being able to make better decisions for tuning the application environment, for selecting the appropriate middleware, and also for designing more powerful middleware systems to efficiently build and run highly complex applications in both parallel and distributed computing environments.
12515507
Using content-addressable networks for load balancing in desktop grids
Desktop grids have evolved to combine Peer-to-Peer and Grid computing techniques to improve the robustness, reliability and scalability of job execution infrastructures. However, efficiently matching incoming jobs to available system resources and achieving good load balance in a fully decentralized and heterogeneous computing environment is a challenging problem. In this paper, we extend our prior work with a new decentralized algorithm for maintaining approximate global load information, and a job pushing mechanism that uses the global information to push jobs towards underutilized portions of the system. The resulting system more effectively balances load and improves overall system throughput. Through a comparative analysis of experimental results across different system configurations and job profiles, performed via simulation, we show that our system can reliably execute Grid applications on a distributed set of resources both with low cost and with good load balance.
1972714
Fast color image processing using quantized color instruction set
The paper describes the Quantized Color Pack eXtension (QCPX) instruction set that can accelerate color-image processing applications. QCPX employs heterogeneous-subword-parallel instructions, which utilize the microprocessor's 16-bit wide datapaths to process a packed, quantized 16-bit color data type in YCbCr (Y: luminance, Cr and Cb: chrominance) format in parallel. Unlike typical multimedia instruction set extensions (e.g. MMX, SSE, ALTIVEC), QCPX obtains performance and code density improvements through implicit support for color pixel processing rather than depending solely upon generic subword parallelism. Five time-critical color image processing algorithms are coded with and without QCPX to fully measure its impact upon programming techniques. Simulation results indicate that the applications using QCPX achieve significant speedups in execution time over non-QCPX. In addition, QCPX results in higher system utilization (in excess of 94% in all cases) due to significant reduction of conditional instructions.
701944
Simulation-Based Security Testing for Continuity of Essential Service
One of the most important characteristic of essential service in the computer network is its continuity. If the continuity of essential service is not guaranteed, it causes a big problem in normal operation of computer network. In our research, we suggest the simulation-based security testing for the continuity of essential service. Especially, the security testing sequence and Experimental Frame is designed to get indexes related to the continuity of essential service. We choose three testing indexes that represent the degree of service continuity and testing methods to get those indexes. Also, to explain the indexes and the testing methods, two testing examples are presented.
41170703
Development of the Efficient OWL Document Management System for the Embedded Applications
To provide ontology-based context understanding services in the embedded application areas, efficient ontology document management schemes are required. Even though some related systems have been developed, they are not appropriate for the embedded system environment with some limitations on memory, disk space and computing power, such as home networking, telematics and intelligent robotics. In this regard, we have developed the embedded system-oriented OWL semantic document management system using the relational databases. We first design a relational data schema appropriate for the OWL documents and then develop a transformation mechanism to store OWL documents. Additionally, the RDQL semantic query processor is additionally implemented for the experiments.
62653029
The BlackWidow High-Radix Clos Network
This paper describes the radix-64 folded-Clos network of the Cray BlackWidow scalable vector multiprocessor. We describe the BlackWidow network which scales to 32K processors with a worstcase diameter of seven hops, and the underlying high-radix router microarchitecture and its implementation. By using a high-radix router with many narrow channels we are able to take advantage of the higher pin density and faster signaling rates available in modern ASIC technology. The BlackWidow router is an 800 MHz ASIC with 64 18.75Gb/s bidirectional ports for an aggregate offchip bandwidth of 2.4Tb/s. Each port consists of three 6.25Gb/s differential signals in each direction. The router supports deterministic and adaptive packet routing with separate buffering for request and reply virtual channels. The router is organized hierarchically [13] as an 8�8 array of tiles which simplifies arbitration by avoiding long wires in the arbiters. Each tile of the array contains a router port, its associated buffering, and an 8�8 router subswitch. The router ASIC is implemented in a 90nm CMOS standard cell ASIC technology and went from concept to tapeout in 17 months.
15504838
Utilization-based heuristics for statically mapping real-time applications onto the HiPer-D heterogeneous computing system
Real-time applications continue to increase in importance as they are employed in various critical areas, such as command and control systems. These applications have traditionally required custom-made systems to execute them. Recently, with the widespread use of increasingly powerful commercial off-the-shelf (COTS) products, some real-time system designers have started a shift from custom development to COTS-based systems to achieve lower costs and more flexible systems. This research investigates the problem of allocating real-time applications to a set of COTS heterogeneous machines connected together by a COTS high-speed network. The heuristics were implemented on the High Performance Distributed Computing Program's (HiPer-D) Naval Surface Warfare Center (NSWC) testbed. At the specification of NSWC, the goal of this study is to design static resource allocation heuristics that balance the utilization of the computation and network resources in the HiPer-D system based on the system information provided. The broader goal is to maximize the time before dynamic reallocation is required for managing an increased workload at runtime.