Ariel Goyeneche

GEMLCA: Running Legacy Code Applications as Grid Services

There are many legacy code applications that cannot be run in a Grid environment without significant modification. To avoid re-engineering of legacy code, we developed the Grid Execution Management for Legacy Code Architecture (GEMLCA) that enables deployment of legacy code applications as Grid services. GEMLCA implements a general architecture for deploying legacy applications as Grid services without the need for code re-engineering, or even access to the source files. With GEMLCA, only a user-level understanding is required to run a legacy application from a standard Grid service client. The legacy code runs in its native environment using the GEMLCA resource layer to communicate with the Grid client, thus hiding the legacy nature of the application and presenting it as a Grid service. GEMLCA as a Grid service layer supports submitting jobs, getting their results and status back. The paper introduces the GEMLCA concept, its life cycle, design and implementation. It also presents as an example a legacy simulation code that has been successfully transformed into a Grid service using GEMLCA.

High-level grid application environment to use legacy codes as OGSA grid services

One of the biggest obstacles in the wide-spread industrial take-up of grid technology is the existence of a large amount of legacy code that is not accessible as grid services. The paper describes a new approach (GEMLCA: grid execution management for legacy code architecture) to deploy legacy codes as grid services without modifying the original code. Moreover, we show a workflow execution oriented grid portal technology (P-GRADE portal) by which such legacy code based grid services can be applied in complex business processes. GEMLCA has been implemented as GT-3 services but can be easily ported into the new WSRF grid standards.

GEMLCA: grid execution management for legacy code architecture design

The grid execution management for legacy code architecture (GEMLCA) describes a solution for exposing and executing legacy applications through an OGSI grid service. This architecture has been introduced in a previous paper by the same authors where the general concept was demonstrated by creating an OGSI/GT3 version of the MadCity traffic simulator. The class structure of the architecture is described presenting each component and describing the relationships between them. Also, the current architecture implementation is evaluated through test results gained by running the MadCity traffic simulator as a C/PVM legacy application.

The Grid Backfilling: a Multi-Site Scheduling Architecture with Data Mining Prediction Techniques

In large Grids, like the National Grid Service (NGS), or large distributed architecture different scheduling entities are involved. Despite a global scheduling approach would archive higher performance and could increment the utilization of global system in these scenarios usually independent schedulers carry out its own scheduling decisions. In this paper we present how a coordinated scheduling among all the different centers using data mining prediction techniques can substantially improve the performance of the global distributed infrastructure, and can provide a uniform access to the user to all the heterogeneous Grid resources. We present the Grid Backfilling meta-scheduling policy that optimizes the global utilization of the system resources and increases substantially the response time for the jobs. We also present how data mining techniques applied to historical information can provide very suitable inputs for carrying out the Grid Backfilling meta-scheduling decisions.

Traffic Simulation in P-Grade as a Grid Service

Grid Execution Management for Legacy Code Architecture (GEMLCA) is a general architecture to deploy existing legacy applications as Grid services without re-engineering the original code. Using GEMLCA from the P-Grade portal, legacy code programs can be accessed as Grid services and even participate in complex Grid workflows. The parallel version of MadCity, a discrete time-based traffic simulator, was created using P-Grade. This paper describes how MadCity is offered as a Grid service using GEMLCA and how this solution is embedded into the P-Grade portal.

Publishing and Executing Parallel Legacy Code Using an OGSI Grid Service

This paper describes an architecture for publishing and executing parallel legacy code using an OGSI Grid service. A framework is presented that aids existing legacy applications to be deployed as OGSI Grid services and the concept is demonstrated by creating an OGSI/GT3 version of the Westminster MadCity traffic simulator application. This paper presents the Grid Execution Management for Legacy Code Architecture (GEMLCA), and describes the progress and achievements of its implementation.

Experiences with deploying legacy code applications as grid services using GEMLCA

One of the biggest obstacles in the wide-spread industrial take-up of Grid technology is the existence of a large amount of legacy code programs that is not accessible as Grid Services. On top of that, Grid technology challenges the user in order to intuitively interconnect and utilize resources in a friendly environment. This paper describes how legacy code applications were transformed into Grid Services using GEMLCA providing a user-friendly high-level Grid environment for deployment, and running them through the P-GRADE Grid portal. GEMLCA enables the use of legacy code programs as Grid services without modifying the original code. Using the P-GRADE Grid portal with GEMLCA it is possible to deploy legacy code applications as Grid services and use them in the creation and execution of complex workflows. This environment is tested by deploying and executing several legacy code applications on different sites of the UK e-Science OGSA testbed.

Security mechanisms for legacy code applications in GT3 environment

There are many legacy code applications that cannot be run in grid environment without significant modifications. To avoid reengineering of legacy code, we developed the grid execution management for legacy code architecture (GEMLCA) that enables deployment of legacy code applications as grid services. GEMLCA is an OGSI grid service layer that supports submitting jobs, getting their results and status back. Security requirements are essential to any grid application to preserve the confidentiality and integrity of data. To meet these requirements the GT3 security model was implemented in GEMLCA. The paper introduces GEMLCA and how grid security infrastructure (GSI) components have been added to GEMLCA in order to enable secure execution of jobs in grid. The paper also presents how a legacy code traffic simulator was transformed into a grid service using GEMLCA and gives some simulation results.