Róbert Lovas

P-GRADE: a grid programming environment

P-GRADE provides a high-level graphical environment to develop parallel applications transparently both for parallel systems and the Grid. P-GRADE supports the interactive execution of parallel programs as well as the creation of a Condor, Condor-G or Globus job to execute parallel programs in the Grid. In P-GRADE, the user can generate either PVM or MPI code according to the underlying Grid where the parallel application should be executed. PVM applications generated by P-GRADE can migrate between different Grid sites and as a result P-GRADE guarantees reliable, fault-tolerant parallel program execution in the Grid. The GRM/PROVE performance monitoring and visualisation toolset has been extended towards the Grid and connected to a general Grid monitor (Mercury) developed in the EU GridLab project. Using the Mercury/GRM/PROVE Grid application monitoring infrastructure any parallel application launched by P-GRADE can be remotely monitored and analysed at run time even if the application migrates among Grid sites. P-GRADE supports workflow definition and co-ordinated multi-job execution for the Grid. Such workflow management can provide parallel execution at both inter-job and intra-job level. Automatic checkpoint mechanism for parallel programs supports the migration of parallel jobs inside the workflow providing a fault-tolerant workflow execution mechanism. The paper describes all of these features of P-GRADE and their implementation concepts.

EDGeS: Bridging EGEE to BOINC and XtremWeb

Desktop Grids, such as XtremWeb and BOINC, and Service Grids, such as EGEE, are two different approaches for science communities to gather computing power from a large number of computing resources. Nevertheless, little work has been done to combine these two Grid technologies in order to establish a seamless and vast Grid resource pool. In this paper we present the EGEE Service Grid, the BOINC and XtremWeb Desktop Grids. Then, we present the EDGeS solution to bridge the EGEE Service Grid with the BOINC and XtremWeb Desktop Grids.

Workflow Support for Complex Grid Applications: Integrated and Portal Solutions

In this paper we present a workflow solution to support graphically the design, execution, monitoring, and performance visualisation of complex grid applications. The described workflow concept can provide interoperability among different types of legacy applications on heterogeneous computational platforms, such as Condor or Globus based grids. The major design and implementation issues concerning the integration of Condor tools, Mercury grid monitoring infrastructure, PROVE performance visualisation tool, and the new workflow layer of P-GRADE are discussed in two scenarios. The integrated version of P-GRADE represents the thick client concept, while the portal version needs only a thin client and can be accessed by a standard web browser. To illustrate the application of our approach in the grid, an ultra-short range weather prediction system is presented that can be executed in a grid testbed and visualised not only at workflow level but at the level of individual parallel jobs, too.

The P-GRADE Grid Portal

Providing Grid users with a widely accessible, homogeneous and easy-to-use graphical interface is the foremost aim of Grid-portal development. These portals if designed and implemented in a proper and user-friendly way, might fuel the dissemination of Grid-technologies, hereby promoting the shift of Grid-usage from research into real life, industrial application, which is to happen in the foreseeable future, hopefully. This paper highlights the key issues in Grid-portal development and introduces P-GRADE Portal being developed at MTA SZTAKI. The portal allows users to manage the whole life-cycle of executing a parallel application in the Grid: editing workflows, submitting jobs relying on Grid-credentials and analyzing the monitored trace-data by means of visualization.

The GRED graphical editor for the GRADE parallel program development environment

Abstract In this paper, we describe a graphical editor GRED as a part of the integrated programing environment GRADE that is intended to support designing, debugging and performance tuning of message-passing programs running on a heterogeneous network of computers. The GRED editor hides the cumbersome details of the underlying low-level message-passing system (which can be either PVM or MPI) by providing visual abstractions but allows the programer to define local computations of the individual processes in C (or in Fortran in the future) independently from the visually supported process management and inter-process communication activities. Visual representation of the critical (i.e. message-passing related) parts of the code can help the user in grasping the complex structure and run-time behavior of the whole parallel application, even if he or she is not an expert in the field of concurrent programing.

EDGeS: The common boundary between service and desktop grids

Service grids and desktop grids are both promoted by their supportive communities as great solutions for solving the available compute power problem and helping to balance loads across network systems. Little work, however, has been undertaken to blend these two technologies together. In this paper we introduce a new EU project, that is building technological bridges to facilitate service and desktop grid interoperability. We provide a taxonomy and background into service grids, such as EGEE and desktop grids or volunteer computing platforms, such as BOINC and XtremWeb. We then describe our approach for identifying translation technologies between service and desktop grids. The individual themes discuss the actual bridging technologies employed and the distributed data issues surrounding deployment.

Application of P-Grade Development Environment in Meteorology

The main objective of a meteorological nowcasting system is to analyse and predict in ultra short range those weather phenomena, which might be dangerous for life and property. The Hungarian Meteorological Service developed a nowcasting system, called MEANDER and its most computational intensive calculations have been parallelised by the help of P-GRADE graphical programming environment. In order to demonstrate the efficient application of P-GRADE in real-size problems we give an overview on the parallelisation of MEANDER system using the P-GRADE environment at the different stages of parallel program development; design, debugging and performance analysis.

Unified Development Solution for Cluster and Grid Computing and Its Application in Chemistry

P-GRADE programming environment provides high-level graphical support to develop parallel applications transparently for both the parallel systems and the Grid. This paper gives an overview on the parallelisation of a simulation algorithm for chemical reaction-diffusion systems applying P-GRADE environment at all stages of parallel program development cycle including the design, the debugging, the execution, and the performance analysis. The automatic checkpoint mechanism for parallel programs, which supports the migration of parallel jobs between different clusters, together with the application monitoring facilities of P-GRADE enable the long-running parallel jobs to run on various non-dedicated clusters in the Grid while their execution can be visualised on-line for the user. The presented research achievements will be deployed in a chemistry Grid environment for air pollution forecast.

Systematic Debugging of Parallel Programs in DIWIDE Based on Collective Breakpoints and Macrosteps

The paper introduces the concept of collective breakpoints and macrosteps. Based on the collective breakpoints the macrostep-by-macrostep execution mode has been defined. After introducing the concept of the execution tree and meta-breakpoints the systematic debugging of message passing parallel programs is explained. The main features and distributed structure of DIWIDE, a macrostep debugger is described. The integration of DIWIDE into the GRADE and WINPAR parallel programming environments is outlined.

Boosting gLite with cloud augmented volunteer computing

The paper details the result of the EU FP7 EDGI project focusing on the cloud developments and usability improvements. Volunteer desktop grids, like BOINC, are designed to handle millions of parameter sweep type jobs and millions of desktop machines as worker nodes. Seamless transfer of gLite jobs to desktop grids was already implemented by EDGI; however this huge number of DG resources could not be utilized efficiently due to slow completion time caused by unpredictable behavior of the volunteer resources. The paper details how clouds have been utilized to shorten completion time on the EDGeS@home volunteer desktop grid to boost the performance of the supported gLite VO and also details how this service can be exploited by the gLite user communities of EGI (European Grid Initiative) all over Europe. One of the aims of EDGI project is to integrate gLite and BOINC systems.Volunteer resources provides a huge computational capacity that can be utilized by gLite users.Untrusted/unstable volunteer resources ends up in tail-effect causing longer completion time.Integrated cloud resource eliminates tail and reduces completion time significantly.Algorithm is designed to recognize and to redirect workunits causing the tail.