Effective reuse of coupling technologies for Earth System Models

Dunlap, Ralph S.

Title:

Effective reuse of coupling technologies for Earth System Models

dc.contributor.advisor	Rugaber, Spencer
dc.contributor.advisor	Mark, Leo
dc.contributor.author	Dunlap, Ralph S.
dc.contributor.committeeMember	Bader, David
dc.contributor.committeeMember	Navathe, Shamkant
dc.contributor.committeeMember	Balaji, Venkatramani
dc.contributor.department	Computer Science
dc.date.accessioned	2013-09-16T18:34:41Z
dc.date.available	2013-09-16T18:34:41Z
dc.date.created	2013-08
dc.date.issued	2013-05-13
dc.date.submitted	August 2013
dc.date.updated	2013-09-16T18:34:41Z
dc.description.abstract	Designing and implementing coupled Earth System Models (ESMs) is a challenge for climate scientists and software engineers alike. Coupled models incorporate two or more independent numerical models into a single application, allowing for the simulation of complex feedback effects. As ESMs increase in sophistication, incorporating higher fidelity models of geophysical processes, developers are faced with the issue of managing increasing software complexity. Recently, reusable coupling software has emerged to aid developers in building coupled models. Effective reuse of coupling infrastructure means increasing the number of coupling functions reused, minimizing code duplication, reducing the development time required to couple models, and enabling flexible composition of coupling infrastructure with existing constituent model implementations. Despite the widespread availability of software packages that provide coupling infrastructure, effective reuse of coupling technologies remains an elusive goal: coupling models is effort-intensive, often requiring weeks or months of developer time to work through implementation details, even when starting from a set of existing software components. Coupling technologies are never used in isolation: they must be integrated with multiple existing constituent models to provide their primary services, such as model-to-model data communication and transformation. Unfortunately, the high level of interdependence between coupling concerns and scientific concerns has resulted in high interdependence between the infrastructure code and the scientific code within a model’s implementation. These dependencies are a source of complexity which tends to reduce reusability of coupling infrastructure. This dissertation presents mechanisms for increasing modeler productivity based on improving reuse of coupling infrastructure and raising the level of abstraction at which modelers work. This dissertation argues that effective reuse of coupling technologies can be achieved by decomposing existing coupling technologies into a salient set of implementation-independent features required for coupling high-performance models, increasing abstraction levels at which model developers work, and facilitating integration of coupling infrastructure with constituent models via component-based modularization of coupling features. The contributions of this research include: (1) a comprehensive feature model that identifies the multi-dimensional design space of coupling technologies used in high-performance Earth System Models, (2) Cupid, a domain-specific language and compiler for specifying coupling configurations declaratively and generating their implementations automatically, and (3) Component-based Coupling Operators (CC-Ops), a modular approach to code reuse of coupling infrastructure based on component technologies for high-performance scientific settings. The Cupid domain-specific language is evaluated by specifying a coupling configuration for an example fluid dynamics model and measuring the amount of code generated by the Cupid compiler compared to a hand coded version. The CC-Op approach is evaluated by implementing several CC-Ops using an existing high-performance component framework and measuring performance in terms of scalability and overhead.
dc.description.degree	Ph.D.
dc.format.mimetype	application/pdf
dc.identifier.uri	http://hdl.handle.net/1853/48943
dc.language.iso	en_US
dc.publisher	Georgia Institute of Technology
dc.subject	Coupled models
dc.subject	Coupling
dc.subject	Earth system model
dc.subject	Software reuse
dc.subject	Component-based software engineering
dc.subject	Domain-specific language
dc.subject	Feature modeling
dc.subject.lcsh	Earth sciences
dc.subject.lcsh	Computer simulation
dc.subject.lcsh	Coupled problems (Complex systems)
dc.subject.lcsh	System analysis
dc.subject.lcsh	Computer software Reusablility
dc.title	Effective reuse of coupling technologies for Earth System Models
dc.type	Text
dc.type.genre	Dissertation
dspace.entity.type	Publication
local.contributor.advisor	Rugaber, Spencer
local.contributor.corporatename	School of Chemical and Biomolecular Engineering
local.contributor.corporatename	College of Engineering
relation.isAdvisorOfPublication	6eef26c6-8f7b-4efa-800b-6c1ab2fec381
relation.isOrgUnitOfPublication	6cfa2dc6-c5bf-4f6b-99a2-57105d8f7a6f
relation.isOrgUnitOfPublication	7c022d60-21d5-497c-b552-95e489a06569
thesis.degree.level	Doctoral