Service-enabling Legacy Applications for the GENIE Project

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Service-enabling Legacy Applications for the
GENIE Project

• Sofia Panagiotidi, Jeremy Cohen, John Darlington,
  Marko Krznaric and Eleftheria Katsiri

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Motivation

• Engineer GENIE to inform research on component
  coupling frameworks
• Analysis of a complicated piece of code such as
  GENIE
• Extraction of interface and model coupling
  semantics
• Modern component architectures indicate the need
  for highly engineered and autonomous components
• Create methodology to advance the quality of
  functional code

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Goals

• A flexible coupling framework where components
  can be individually developed and coupled
  together
• The coupling needs to be correct, intelligent and
  without undue programming effort
• Come up with sophisticated ways to couple
  physical entities in order to optimally produce
  experimental results
• A system of the size and complexity of GENIE
  requires a supporting semantic framework

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Previous Work

• Separation of the code into pieces - Layered
  representation of the application
• Wrapping GENIE as ICENI binary component
• Delivery of Web-based System (portal) to allow a
  virtual organisation of environmental scientists
  to create and manage simulations at a high-level
  over a Condor pool
• Implementation of database management system to
  allow scientists to share, access and visualise
  data produced by simulation runs
• Investigation of model-coupling and validation
  semantics

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GENIE model framework
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Currently in GENIE

• genie.F is a glorified metafile containing
  if-then-else statements
• Fortran routines act as wrappers
• Life cycle phases scattered
• Module communication through shared memory
• Hard-coded semantics (e.g. grid interpolations,
  time steps)

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Extended Abstract Component (Grid) Model for GENIE

• Model Specific Interfaces
• Abstract Interface - Plugin adapters
• Web Service Wrapper Layer
• Communication through SOAP/MPI
• Metadata for Composability

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Componentising GENIE

• Determining I/Os
• SIDL (Scientific Interface Description Language)
  - Common way of describing components
• Linking Fortran to Java
• Babel Interoperability Tool
• Shared Libraries

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Babel Interoperability Tool
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Steps to Service Enable GENIE (1/4)

• 1. Wrap and test modules individually
• 2. Test module communication through an
  equivalent to genie.F Java client compare
  results
• 3. Create Abstract Component Interfaces

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Steps to Service Enable GENIE (2/4)

• 4. Launch components as Web Services and modify
  Java client to now call Web Services instead

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Steps to Service Enable GENIE (3/4)

• 5.Use workflow engine to orchestrate the Abstract
  Components

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Steps to Service Enable GENIE (4/4)

• 6. Advance into a Grid environment so as to
  incorporate Co-ordination Specification, Dynamic
  Abstract Generator, Resource Allocation and
  Optimisation

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An example as proof of concept
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Achieved..
Web Service Client
Embm Bean
Embm Atmosphere
Surflux Bean
Surflux
GoldSeaice Bean
Land Bean
Goldstein Seaice
Land
Goldstein Bean
Goldstein Ocean
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Conclusions

• Provided service-based computational Grid
  execution architecture for GENIE framework
• Scaled engineering steps
• Proved that functional legacy code can be
  distributed and run as Web Services

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