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...

The original specification for the Message Passing Interface (MPI) included language bindings for C and Fortran 77. C++ programs that used MPI were thus required to use the C bindings. With MPI-2, a C++ interface for all of MPI is specified. In this paper, we describe the design of the C++ interface for MPI and provide some of the history and motivations behind the design decisions.

BACKGROUND Although high exercise tolerance is associated with an excellent prognosis, the significance of abnormal myocardial perfusion imaging (MPI) in patients with high exercise tolerance has not been established. This study retrospectively compares the utility of MPI and exercise ECG (EECG) in these patients. METHODS AND RESULTS Of 388 consecutive patients who underwent exercise MPI and ...

BACKGROUND Exercise electrocardiography (ETT) is frequently used in patients with suspected coronary artery disease (CAD). Single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) improves diagnostic stratification. There are no randomized trials comparing ETT and MPI. We hypothesized that first-line MPI would be effective and cost-saving versus ETT. METHODS AND R...

Petascale machines with close to a million processors will soon be available. Although MPI is the dominant programming model today, some researchers and users wonder (and perhaps even doubt) whether MPI will scale to such large processor counts. In this paper, we examine this issue of how scalable is MPI. We first examine the MPI specification itself and discuss areas with scalability concerns ...