. We present our MPI-BIP implementation, designed for Myrinet networks, and based on MPICH. By using our Basic Interface for Parallelism: BIP software layer, we obtain in this implementation of the MPI protocols results close to the peak hardware performance of the high speed Myrinet network. We present the protocols we used to implement the MPI semantics, and the overall design of the implementation. We, then, present benchmarks and application results to show that this design leads to parallel multicomputer-like throughput and latency on a cluster of PC workstations. 1 Introduction In the last decade, researchers tried to use COWs (Cluster Of Workstations) as parallel computers. These clusters are typically connected by Ethernet networks and are often programmed with communication libraries like PVM (Parallel Virtual Machine [6]), or MPI over IP (Internet Protocol). There is two bottlenecks in these solutions that can restrict application programmers to coarse grain paral...

We present buered coscheduling, a new methodology to multitask parallel jobs in a message-passing environment and to develop parallel programs that can pave the way to the efficient implementation of a distributed operating system. Buffered coscheduling is based on three innovative techniques: communication buffering, strobing, and non-blocking communication. By leveraging these techniques, we can perform effective optimizations based on the global status of the parallel machine rather than on the limited knowledge available locally to each processor. The advantages of buffered coscheduling include higher resource utilization, reduced communication overhead, efficient implementation of flow-control strategies and fault-tolerant protocols, accurate performance modeling, and a simplied yet still expressive parallel programming model which offloads many resource-management tasks to the operating system. Preliminary experimental results show that buffered coscheduling is very effective in inc...

Compiled communication has recently been proposed to improve communication performance for clusters of workstations. The idea of compiled communication is to apply more aggressive optimizations to communications whose information is known at compile time. Existing MPI libraries do not support compiled communication. In this paper, we present an MPI prototype, CC--MPI, that supports compiled communication on Ethernet switched clusters. The unique feature of CC--MPI is that it allows the user to manage network resources such as multicast groups directly and to optimize communications based on the availability of the communication information. CC--MPI optimizes one--to--all, one--to-- many, all--to--all, and many--to--many collective communication routines using the compiled communication technique. We describe the techniques used in CC--MPI and report its performance. The results show that communication performance of Ethernet switched clusters can be significantly improved through compiled communication.

this paper is organized as follows. In Section 2, we describe the basic support for concurrent computing/programming provided by Java, as well as some other features that are relevant to understand the proposals described here. Readers that are familiar with Java's concurrency features can skip this section. In Section 3, we describe the parameters chosen to classify each of the selected projects. In Section 4, we describe the Java environments and mechanisms for supporting high-performance network-based computing that were included in this survey. Section 5 presents a classi cation of these systems, based on the parameters described in Section 3. Section 6 concludes this work

We have implemented a system called MPI-NP II, vhich is an MPI specific messaging system for the Myrinet System Area Netvorks (SAN). It consists of a lov- level message manager executing on the LANai processor of the Myrinet Netsyork Interface Card (NIC), a thin host interface layer, and LAM-MPI, a public domain version of MPI.