The MultiCluster Model to the Integrated Use of Multiple Workstation Clusters

. One of the new research tendencies within the well-established cluster computing area is the growing interest in the use of multiple workstation clusters as a single virtual parallel machine, in much the same way as individual workstations are nowadays connected to build a single parallel cluster. In this paper we present an analysis on several aspects concerning the integration of different workstation clusters, such as Myrinet and SCI, and propose our MultiCluster model as an alternative to achieve such integrated architecture. 1 Introduction Cluster computing is nowadays a common practice to many research groups around the world that search for high performance to a great variety of parallel and distributed applications, like aerospacial and molecular simulations, Web servers, data mining, and so forth. To achieve high performance, many efforts have been devoted to the design and implementation of low overhead communication libraries, specially dedicated to fast communicat..

Improving Reactivity to I/O Events in Multithreaded Environments Using a Uniform, Scheduler-Centric API

Reactivity to I/O events is a crucial factor for the performance of modern multithreaded distributed systems. In our scheduler-centric approach, an application detects I/O events by requesting a service from a detection server, through a simple, uniform API. We show that a good choice for this detection server is the thread scheduler. This approach simplifies application programming, significantly improves performance, and provides a much tighter control on reactivity

Parallel 3D air flow simulation on workstation clusters

Thesee is a 3D panel method code, which calculates the characteristic of a wing in an inviscid, incompressible, irrotational, and steady airflow, in order to design new paragliders and sails. In this paper, we present the parallelization of Thesee for low cost workstation /PC clusters. Thesee has been parallelized using the ScaLAPACK library routines in a systematic manner that lead to a low cost development. The code written in C is thus very portable since it uses only high level libraries. This design was very efficient in term of manpower and gave good performance results. The code performances were measured on 3 clusters of computers connected by different LANs: an Ethernet LAN of SUN SPARCstation, an ATM LAN of SUN SPARCstation and a Myrinet LAN of PCs. The last one was the less expensive and gave the best timing results and super-linear speedup

Efficient Multidimensional Data Redistribution for Resizable Parallel Computations

Traditional parallel schedulers running on cluster supercomputers support only static scheduling, where the number of processors allocated to an application remains fixed throughout the execution of the job. This results in underutilization of idle system resources thereby decreasing overall system throughput. In our research, we have developed a prototype framework called ReSHAPE, which supports dynamic resizing of parallel MPI applications executing on distributed memory platforms. The resizing library in ReSHAPE includes support for releasing and acquiring processors and efficiently redistributing application state to a new set of processors. In this paper, we derive an algorithm for redistributing two-dimensional block-cyclic arrays from P to Q processors, organized as 2-D processor grids. The algorithm ensures a contention-free communication schedule for data redistribution if Pr ≤ Qr and Pc ≤ Qc. In other cases, the algorithm implements circular row and column shifts on the communication schedule to minimize node contention