Fast hardware turnover in supercomputing centers, stimulated by rapid technological progress, results in high heterogeneity among HPC platforms, and necessitates that applications are ported and adapted frequently. The cutting-edge nature of the hardware mandates customized performance tuning, which, coupled with continuously growing application complexity, makes the process inherently and increasingly challenging. In this paper, we analyze build procedures of a representative set of HPC applications, and attempt to identify commonalities that can be exploited to enhance cross-platform portability. We then propose a novel method for reducing non-portabilities while preserving high performance. The approach, based on profiles that capture and isolate non-portable features at various levels, requires only a moderate amount of changes to existing makefiles. It leverages the expertise of system designers and administrators, and reduces burdens placed on application scientists. As a proof of concept, we discuss the application of our methodology to enhancing portability of the Mile application across heterogeneous HPC platforms.

Heterogeneous distributed computing platforms continue to require substantial effort in terms of software installation and management for efficient use, often necessitating manual intervention by resource providers and end-users. In this paper we propose a novel model of resource sharing that is a viable alternative to that commonly adopted in the grid community. Our model shifts the resource virtualization and aggregation responsibilities to software at the client side, taking these burdens away from resource providers. Following this model, we have designed the Zero-Force MPI toolkit that automates installation, run, and post-processing stages of HPC applications, thus allowing application scientists to focus on using computational resources instead of managing them. Through the provided console, MPI can be soft-installed across a set of distributed resources with just a few commands. The prototype implementation of the ZF-MPI toolkit is based on FTMPI. To evaluate the toolkit, we conducted experiments with deploying and executing the NAS Parallel Benchmarks. Results demonstrate that the run-not-install approach exemplified by ZF-MPI is effective and may substantially increase productivity of application execution.

The capability to announce and discover resources is a foundation for heterogeneous computing systems. Independent projects have adopted custom implementations of information services, which are not interoperable and induce substantial maintenance costs. In this paper, we propose an alternative methodology. We suggest that it is possible to reuse existing naming service deployments and combine them into complex, scalable, hierarchical, distributed federations, by using appropriate client-side integration middleware that unifies service access and hides heterogeneity behind a common API. We investigate a JNDI-based approach, and describe in detail two newly implemented JNDI service providers, which enable unified access to 1) Jini lookup services, and 2) harness distributed naming services. We claim that these two technologies, along with others already accessible through JNDI such as e.g. DNS and LDAP, offer features suitable for use in hierarchical heterogeneous information systems.

Shared HPC platforms continue to require substantial effort for software installation and management, often necessitating manual intervention and tedious procedures. We propose a novel model of resource sharing that shifts resource virtualization and aggregation responsibilities to client-side software, thus reducing the burdens on resource providers.The Zero-Force MPI toolkit automates the installation, build, run, and post-processing stages of HPC applications, thus allowing application scientists to focus on using resources instead of managing them. Through a provided console, MPI runtime systems, support libraries, application executables, and needed datafiles can be soft-installed across distributed resources with just a few commands. Built-in data synchronization capabilities simplify common HPC development tasks, saving end-user time and effort. To evaluate ZF-MPI, we conducted experiments with the NAS Parallel Benchmarks. Results demonstrate that the proposed run-not-install approach is effective and may substantially increase overall productivity.

Summary form only given. Remote method invocation is one of the most popular communication paradigms in distributed computing. However, its synchronous nature may affect application performance. Asynchronous, or nonblocking, RMI addresses the issue by implicitly introducing concurrency into an application and allowing it to interleave computations with communications. We analyze certain semantic issues raised by asynchronous RMI, such as execution order, exception handling, cancellation, data consistency, and more. Solutions are proposed, and a realization of asynchronous RMI within our multiprotocol, extensible communication framework for Java (termed RMIX), is presented.

Summary form only given. Service-based modalities are becoming more prevalent in metacomputing and grid computing. The absence of preexisting client-server relationships imply the use of standardized, self-describing protocols, which typically suffer from performance deficiencies. The RMIX framework is designed to permit heterogeneous entities to interact via a service-based paradigm while enabling protocol selection and dynamic protocol switching. In particular, an RPC-compliant communication provider enables multilanguage heterogeneous clients to communicate with servers and leverage well-established RPC/XDR mechanisms to support interoperability without sacrificing performance. We describe the RMIX-RPCX communication substrate, and presents preliminary results that suggest its potential value in enhancing service-oriented heterogeneous metacomputing.

This paper describes the Harness-PVM emulation module that makes it possible to run legacy PVM applications within the Harness metacomputing system environment. We show benchmark results suggesting that component- and Java-based frameworks may provide substantial benefits without significantly compromising performance. Augmenting or implementing grids using such component based systems can thus be advantageous in a number of situations.

Software infrastructures that support metacomputing are evolving from traditional monolithic, platform-specific systems to component and service-based frameworks. We demonstrate that contrary to popular belief, such modular software systems are capable of delivering good to excellent performance, support legacy as well as new application programming paradigms, and deliver enhanced functionality. The Harness system, a software backplane enabling reconfigurable distributed concurrent computing is used to emulate the PVM programming environment. Numerical kernel benchmarks show that application performance results using the emulator and native versions are within a few percent of each other. Coupled with the ability to leverage pre-existing and specialized modules, our experiences suggest that service-oriented computational grids may be constructed rapidly and effectively via such component-based architectural frameworks that deliver full functionality, without compromising efficiency.

A novel component-based, service-oriented framework for distributed metacomputing is described. Adopting a provider-centric view of resource sharing, this project emphasizes lightweight software infrastructures that maintain a minimal state, and interface to current and emerging distributed computing standards. Resource owners host a software backplane onto which owners, clients, or third-party, resellers may load components or component-suites that deliver value added services without compromising owner security or control. Standards-based descriptions of services facilitate publication and discovery via established schemes. The architecture of the container framework, design of components, security and access control schemes, and preliminary experiences are described in this paper.

Harness is an Java-centric metacomputing system based on a principle of dynamic reconfigurability not only in terms of participating computing resources, but also the capabilities of the virtual machine itself. The central feature of the system is a “plug-in” mechanism built upon Java dynamic class loading services enabling integration of new functionality in the run time. In this paper we describe new flexible, framework based Java class loading techniques and their application in the Harness system. These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.