Abstract

The Virtual Programming Laboratory (VPL) is a Web-based virtual programming environment built based on a client-server architecture. The system can be accessed on any platform (Unix, PC, or Mac) using a standard Java-enabled browser. Software delivery over the Web imposes a novel set of constraints on design. We outline the tradeoffs in this design space, motivate the choices necessary to deliver an application, and detail the lessons learned in the process. We discuss the role of Java and other Web technologies in the realization of the design. VPL facilitates the development and execution of parallel programs. The initial prototype supports high-level parallel programming based on Fortran 90 and High Performance Fortran (HPF), as well as explicit low-level programming with the MPI message-passing interface. Supplementary Java-based platform-independent tools for data and performance visualization are an integral part of the VPL. Pablo SDDF trace files generated by the Pablo performance instrumentation system are used for postmortem performance visualization.

K. Dincer and G. C. Fox, Design Issues in Building Web-based Parallel Programming Environments, iin Proceedings of the Sixth IEEE International Symposium on High Performance Distributed Computing (HPDC-6), Portland, OR, August 5-8, 1997.

Abstract

We exploited the recent advances in Internet connectivity and Web technologies for building Web-based parallel programming environments (WPPEs) that facilitate the development and execution of parallel programs on remote high-performance computers. A Web browser running on the user’s machine provides a user-friendly interface to server-site user accounts and allows the use of parallel computing platforms and software in a convenient manner. The user may create, edit, and execute files through this Web browser interface. This new Web-based client-server architecture has the potential of being used as a future front-end to high-performance computer systems. We discuss the design and implementation of several prototype WPPEs that are currently in use at the Northeast Parallel Architectures Center and the Cornell Theory Center. These initial prototypes support high-level parallel programming with Fortran 90 and High Performance Fortran (HPF), as well as explicit low-level programming with Message Passing Interface (MPI). We detail the lessons learned during the development process and outline the tradeoffs of various design choices in the realization of the design. We especially concentrate on providing server-site user accounts, mechanisms to access those accounts through the Web, and the Web-related system security issues.

Keywords: Parallel programming, programming environments, web security, HPF, MPI, Fortran 90, WWW.

Abstract

Thinking Machines' CM-5 machine is a distributed-memory, message-passing computer. In this paper we devise a performance benchmark for the base and vector units and the data communication networks of the CM-5 machine. We model the communication characteristics such as communication latency and bandwidths of point-to-point and global communication primitives. We show, on a simple Gaussian elimination code, that an accurate static performance estimation of parallel algorithms is possible by using those basic machine properties connected with computation, vectorization, communication, and synchronization. Furthermore, we describe the embedding of meshes or hypercubes on the CM-5 fat-tree topology and illustrate the performance results of their basic communication primitives.

K. Dincer and G. C. Fox, Building a World-Wide Virtual Machine Based on Web and HPCC Technologies, in the Proceedings of Supercomputing 96, Pittsburgh, Penn., Nov. 17-22, 1996.

Abstract

In this paper we report on a parallel/distributed virtual machine prototype called World-Wide Virtual Machine (WWVM) that is designed to attack grand challenge problems beyond the capabilities of a single supercomputer. The prototype is based on emerging Web and existing HPCC technologies and utilizes the pool of Web servers on the internet as a flexible, convenient, and inexpensive metacomputing resource. World-Wide Web supplies a standard open interface to the world regardless of the machine type. Through this interface Web servers can be used either as computation nodes or coordinators managing other connected nodes of the virtual machine. We have constructed a Web-based parallel/distributed programming environment for solving metaproblems consisting of MPI and PVM message-passing programs and High Performance Fortran programs.

K. Dincer and G. C. Fox, A High Performance Fortran Programming Environment on the World-Wide Virtual Machine, In the Proceedings of the Ninth International Conference on Parallel and Distributed Computing Systems, Dijon, France, Sep.25-27, 1996.

Abstract

In today's high performance computing arena there is a strong trend toward building virtual computers from heterogeneous resources on a network. In this paper we describe our experiences in building a parallel/distributed virtual machine called the World-Wide Virtual Machine (WWVM) using Web and High Performance Computing and Communications (HPCC) technologies. We ported our High Performance Fortran (HPF) compilation system onto this virtual platform to provide a Web-based collaboratory HPF programming environment.

Keywords: WWW, HPCC, HPF, PVM, MPI, Perl, heterogeneous computing.

K. Dincer, G. C. Fox, K.A. Hawick, and A. Choudhary, High Performance Fortran and Possible Extensions to Support Conjugate Gradient Algorithms, in Proceedings of Fifth IEEE International Symposium on High Performance Distributed Computing, pp.69--77, Syracuse, NY, Aug. 6-9, 1996.

Abstract

We evaluate the High Performance Fortran (HPF) language for the compact expression and efficient implementation of conjugate gradient iterative matrix-solvers on High-Performance Computing and Communications(HPCC) platforms. We discuss the use of intrinsic functions, data distribution directives and explicitly parallel constructs to optimize performance by minimizing communications requirements in a portable manner. We focus on implementations using the existing HPF definitions but also discuss issues arising that may influence a revised definition for HPF-2. Some of the codes discussed are available on the World Wide Web at http://www.npac.syr.edu/hpfa/, alongwith other educational and discussion material related to applications in HPF.

E. Akarsu, K. Dincer, T. Haupt, and G. C. Fox, Particle-in-Cell Simulation Codes in High Performance Fortran, in the Proceedings of Supercomputing 96, Pittsburgh, Penn., Nov. 17-22, 1996.

Abstract

Particle-in-Cell (PIC) plasma simulation codes model the interaction of charged particles with surrounding electrostatic and magnetic fields. PIC's computational requirements are classified at as one of the grand-challenge problems facing the high-performance community. In this paper we present the implementation of 1-D and 2-D electrostatic PIC codes in High Performance Fortran (HPF) on an IBM SP-2. We used one of the most successful commercial HPF compilers currently available and augmented the compiler's missing HPF functions with extrinsic routines when necessary. We obtained a near linear speed-up in execution time and a performance comparable to the native message-passing implementations on the same platform.

K. Dincer, H. R. Topcuoglu, F. E. Sevilgen, P. D. Coddington, S. Ranka, Parallel Simulation of Dynamically Triangulated Random Surfaces, In the Proceedings of IASTED 8th International Conference on Parallel and Distributed Computing and Systems, pp.476-480, Chicago, IL, Oct. 16-19, 1996.

Abstract

Dynamically triangulated random surfaces (meshes) are used in simulations of random surface models of quantum gravity in physics and cell membranes in biology. Parallel algorithms for random surface simulations require some mechanism to prevent neighboring edges or vertices from being updated simultaneously. We used two methods to determine the independent sets of edges/vertices, one based on parallel graph-coloring algorithms, and the other on active-message-based locking mechanisms. We present results on a 32-node CM-5 machine.

Keywords: Graph-coloring, active-messages, triangulated random surfaces.