Scientific Software Component Technology

Abstract

Executive SummaryWe are developing new software component technology for high-performance parallel scientific computing to address issues of complexity, re-use, and interoperability for laboratory software. Component technology enables cross-project code re-use, reduces software development costs, and provides additional simulation capabilities for massively parallel laboratory application codes. The success of our approach will be measured by its impact on DOE mathematical and scientific software efforts. Thus, we are collaborating closely with library developers and application scientists in the Common Component Architecture forum, the Equation Solver Interface forum, and other DOE mathematical software groups to gather requirements, write and adopt a variety of design specifications, and develop demonstration projects to validate our approach.Numerical simulation is essential to the science mission at the laboratory. However, it is becoming increasingly difficult to manage the complexity of modern simulation software. Computational scientists develop complex, three-dimensional, massively parallel, full-physics simulations that require the integration of diverse software packages written by outside development teams. Currently, the integration of a new software package, such as a new linear solver library, can require several months of effort.Current industry component technologies such as CORBA, JavaBeans, and COM have all been used successfully in the business domain to reduce software development costs and increate software quality. However, these existing industry component infrastructures will not scale to support massively parallel applications in science and engineering. In particular, they do not address issues related to high-performance parallel computing on ASCI-class machines, such as fast in-process connections between components, language interoperability for scientific languages such as Fortran, parallel data redistribution between components, and massively parallel components. While industrial component systems do not directly address scientific computing issues, we leverage existing industry technologies and design concepts whenever possible.Since the mid-year start of this project in FY99, we have focused on the needs of seamless language interoperability in a high-performance environment. Computational scientists are routinely hindered in code re-use by differences in programming languages; for example, a solver library written in C++ can be difficult to call from an applications code written in C or Fortran. Our approach adopts the industry practice of using an Interface Definition Language (IDL) to describe component interfaces in a language-independent manner. We have developed an IDL for scientific applications (SIDL) that focuses on the unique needs of the scientific domain as compared to the business world. We have also created tools that use SIDL descriptions of software components to generate automatically language bindings and code that allows the component to be called easily from ...

Managing Scientific Software Complexity with Bocca and CCA

“…Neither of these options is open to the scientific computing developers of the Common Component Architecture, requiring that it provide a language interoperability layer. This layer, called the Scientific Interface Definition Language (SIDL) [15], is a specification for defining interfaces that can be used to generate interoperable code in a variety of languages. Babel [4] is the SIDL interpreter that the CCA uses currently supporting Fortran 9X, Fortran 77, C, C++, Python and Java.…”