APPLICATIONS IN DAMPVM/DAC

This paper presents a new object oriented framework DAMPVM/DAC which is implemented on top of DAMPVM and provides automatic partitioning of irregular divide-andconquer (DAC) applications at runtime. The processes are then mapped dynamically to processors taking into account their speeds and even loads by other user processes. The paper presents the programming interface (API) of the framework, available tuning mechanisms, internal solutions with respect to automatic partitioning and mapping to processors. Finally, specific parameters, optimization techniques and simulation results are shown for a variety of irregular divide-and-conquer applications. The applications include αβ search, recursive Fibonacci, ⎛ n

Integration of Services into Workflow Applications

Describing state-of-the-art solutions in distributed system architectures, Integration of Services into Workflow Applications presents a concise approach to the integration of loosely coupled services into workflow applications. It discusses key challenges related to the integration of distributed systems and proposes solutions, both in terms of theoretical aspects such as models and workflow scheduling algorithms, and technical solutions such as software tools and APIs.The book provides an in-depth look at workflow scheduling and proposes a way to integrate several different types of service

Development and Tuning of Irregular Divide-and-Conquer Applications in DAMPVM/DAC

Abstract. This work presents implementations and tuning experiences with parallel irregular applications developed using the object oriented framework DAM-PVM/DAC. It is implemented on top of DAMPVM and provides automatic partitioning of irregular divide-and-conquer (DAC) applications at runtime and dynamic mapping to processors taking into account their speeds and even loads by other user processes. New implementations of parallel applications tuned for shortest execution time are investigated. They include £¥ ¤ search, recursive Fibonacci, ¦¨§©� � and finding twin prime numbers in parallel. Various DAC parameters were tuned for specific applications including costs of computing vectors/subtrees, maximum partitioning levels etc. Moreover, the overhead of DAMPVM/DAC compared to sequential implementations is shown including previously implemented adaptive quadrature integration and image recognition.

PVMWebCluster: Integration of PVM Clusters using Web Services and CORBA

Abstract. We propose a new architecture and its implementation called PVMWebCluster which enables easy parallelization of PVM task execution both onto geographically distributed PVM clusters and within them. Task submission is done by calling Web services that negotiate the best cluster(s) for the task and communicate with clusters via CORBA method invocation. PVMWebCluster supports tightly-coupled high performance demanding parallel applications by using PVM/DAMPVM, implements the idea of controlled cluster sharing among users as in grids and multi-tier applications and finally integrates the components using the latest Web services approach. This architecture gives flexibility, easy access for many users through simple code from many languages and operating systems and future development possibilities. We have implemented a testbed application and evaluated it on a testbed platform consisting of four clusters and eight nodes. Multiple copies have been run on the clusters and also parallelized within each of them using DAMPVM also implemented by the author.