The number of multithreaded Message Passing Interface (MPI) implementations and applications is increasing rapidly. We discuss how multithreaded applications can receive messages of unknown size. As is well known, combining MPI Probe/MPI Recv is not threadsafe, but many assume that trivial workarounds exist. We discuss those workarounds and show how they fail in practice by either limiting the ...

The Message Passing Interface (MPI) standard for programming parallel computers is widely used for building both programs and libraries. Two of the strengths of MPI are its support for libraries and the existence of multiple implementations on many platforms. These two strengths are in conflict, however, when an application wants to use libraries built with different MPI implementations. This p...

Dynamic verification methods are the natural choice for debugging real world programs when model extraction and maintenance are expensive. Message passing programs written using the MPI library fall under this category. Partial order reduction can be very effective for MPI programs because for each process, all its local computational steps, as well as many of its MPI calls, commute with the co...

In this paper we discuss the design and use of a fault tolerant MPI (FT-MPI) that handles process failures in a way beyond that of the original MPI static process model. FT-MPI allows the semantics and associated modes of failures to be explicitly controlled by an application via a modified functionality within the standard MPI 1.2 API. Given is an overview of the FT-MPI semantics, architecture...

Future high-performance computing systems may face frequent failures with their rapid increase in scale and complexity. Resilience to faults has become a major challenge for large-scale applications running on supercomputers, which demands fault tolerance support for prevalent MPI applications. Among failure scenarios, process failures are one of the most severe issues as they usually lead to t...

MPI is routinely used for writing parallel applications, but it is not commonly used for writing long-running parallel services, such as parallel file systems or job schedulers. Nonetheless, MPI does have many features that are potentially useful for writing such software. Using the PVFS2 parallel file system as a motivating example, we studied the needs of software that provide persistent para...

Presently, di erent vendors' MPI implementations cannot interoperate directly with each other. As a result, performance of distributed computing across di erent vendors' machines requires use of a single MPI implementation, such as MPICH. This solution may be sub-optimal since it cannot utilize the vendors' own optimized MPI implementations. PVMPI, a software package currently under development...

Objective(s): Inhaled aerocontaminants are removed from the lungs by pulmonary mucociliary transport (MCT) as an important defense mechanism. This study was undertaken to investigate the influence of the surface potential of magnetic nanoparticles (MNPs) on the MCT in murine lungs by use of magnetic particle imaging (MPI).Materials and Methods: Three kinds of MNPs (carboxymethyl dextran m...