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Articles 1 - 4 of 4
Full-Text Articles in Physical Sciences and Mathematics
Scalable Approaches For Supporting Mpi-Io Atomicity, Peter Aarestad, George K. Thiruvathukal, Avery Ching, Alok Choudhary
Scalable Approaches For Supporting Mpi-Io Atomicity, Peter Aarestad, George K. Thiruvathukal, Avery Ching, Alok Choudhary
George K. Thiruvathukal
Scalable atomic and parallel access to noncontiguous regions of a file is essential to exploit high performance I/O as required by large-scale applications. Parallel I/O frameworks such as MPI I/O conceptually allow I/O to be defined on regions of a file using derived datatypes. Access to regions of a file can be automatically computed on a perprocessor basis using the datatype, resulting in a list of (offset, length) pairs. We describe three approaches for implementing lock serving (whole file, region locking, and byterange locking) and compare the various approaches using three noncontiguous I/O benchmarks. We present the details of the …
Scalable Implementations Of Mpi Atomicity For Concurrent Overlapping I/O, Wei-Keng Liao, Alok Choudhary, Kenin Coloma, George K. Thiruvathukal, Lee Ward, Eric Russell, Neil Pundit
Scalable Implementations Of Mpi Atomicity For Concurrent Overlapping I/O, Wei-Keng Liao, Alok Choudhary, Kenin Coloma, George K. Thiruvathukal, Lee Ward, Eric Russell, Neil Pundit
George K. Thiruvathukal
For concurrent I/O operations, atomicity defines the results in the overlapping file regions simultaneously read/written by requesting processes. Atomicity has been well studied at the file system level, such as POSIX standard. In this paper, we investigate the problems arising from the implementation of MPI atomicity for concurrent overlapping write access and provide a few programming solutions. Since the MPI definition of atomicity differs from the POSIX one, an implementation that simply relies on the POSIX file systems does not guarantee correct MPI semantics. To have a correct implementation of atomic I/O in MPI, we examine the efficiency of three …
Natural Xml For Data Binding, Processing, And Persistence, George K. Thiruvathukal, Konstantin Läufer
Natural Xml For Data Binding, Processing, And Persistence, George K. Thiruvathukal, Konstantin Läufer
George K. Thiruvathukal
The article explains what you need to do to incorporate XML directly into your computational science application. The exploration involves the use of a standard parser to automatically build object trees entirely from application-specific classes. This discussion very much focuses on object-oriented programming languages such as Java and Python, but it can work for non-object-oriented languages as well. The ideas in the article provide a glimpse into the Natural XML research project.
Restfs: Resources And Services Are Filesystems, Too, Joseph P. Kaylor, Konstantin Läufer, George K. Thiruvathukal
Restfs: Resources And Services Are Filesystems, Too, Joseph P. Kaylor, Konstantin Läufer, George K. Thiruvathukal
George K. Thiruvathukal
We have designed and implemented RestFS, a software frame-work that provides a uniform, configurable connector layerfor mapping remote web-based resources to local filesystem-based resources, recognizing the similarity between thesetwo types of resources. Such mappings enable programmaticaccess to a resource, as well as composition of two or moreresources, through the local operating system’s standardfilesystem application programming interface (API), script-able file-based command-line utilities, and inter-process com-munication (IPC) mechanisms. The framework supports au-tomatic and manual authentication. We include several ex-amples intended to show the utility and practicality of ourframework.