Abstract: A computer-executable method, system, and computer program product for managing metadata in a distributed data storage system, wherein the distributed data storage system includes a first burst buffer having a key-value store enabled to store metadata, the computer-executable method, system, and computer program product comprising receiving, from a compute node, metadata related to data stored within the distributed data storage system, indexing the metadata at the first burst buffer, and processing the metadata in the first burst buffer.

Abstract: Methods and apparatus are provided for simulating asynchronous modifications of shared data objects by a number of distributed processes within a distributed application. An exemplary method comprises obtaining a plurality of simulation parameters that define parameters of a simulated distributed application, parameters of a plurality of distributed compute nodes on which the simulated distributed application executes and a storage system employed by the simulated distributed application; and applying the plurality of simulation parameters to a simulation engine, wherein the simulation engine simulates both synchronous and asynchronous modifications of at least one shared data object by a plurality of distributed processes within the simulated distributed application.

Abstract: A ground fault tester (GFT) for monitoring ground fault of DC/Battery Powered Equipment is provided. The ground fault tester (GFT) comprises a signal conditioning unit to receive a raw signal (Vs) for monitoring a ground fault and output a voltage signal (Vr), an adjustable threshold module (TH) to provide a threshold voltage (Vth) and a comparator to compare two voltages (Vr), (Vth) and output a signal indicative of the ground fault. The ground fault tester (GFT) further comprises a controller to receive a test request command and output a GFT output. The controller to control a relay device (K) for flowing a calculated test current (Itest) to a ground (GND).

Abstract: A cluster file system comprises a parallel file system and a plurality of burst buffers, with the burst buffers collectively configured to provide an interface between the parallel file system and compute nodes of a computer system. Each of the burst buffers comprises a virtual file system component and a metadata server component. The virtual file system components of respective ones of the burst buffers collectively implement a virtual file system. Metadata relating portions of the virtual file system to portions of the parallel file system is stored in a distributed manner over the metadata server components of the respective burst buffers. Each burst buffer independently manages its own flash memory, but the burst buffers are configured such that data consistency is ensured across their flash memories. The virtual file system illustratively comprises a parallel log-structured file system (PLFS) and the metadata server components illustratively comprise respective TO forwarding servers.

Abstract: A ground fault tester (GFT) for monitoring ground fault of DC/Battery Powered Equipment is provided. The ground fault tester (GFT) comprises a signal conditioning unit to receive a raw signal (Vs) for monitoring a ground fault and output a voltage signal (Vr), an adjustable threshold module (TH) to provide a threshold voltage (Vth) and a comparator to compare two voltages (Vr), (Vth) and output a signal indicative of the ground fault. The ground fault tester (GFT) further comprises a controller to receive a test request command and output a GFT output. The controller to control a relay device (K) for flowing a calculated test current (Itest) to a ground (GND).

Abstract: Techniques are provided for storing data and metadata on sharded storage arrays. In one embodiment, data is processed in a sharded distributed data storage system that stores data in a plurality of shards on one or more storage nodes by providing a plurality of addressable virtual shards within each of the shards, wherein at least a first one of the addressable virtual shards stores the data, and wherein at least a second one of the addressable virtual shards stores the metadata related to the data; obtaining the data from a compute node; and providing the data and the metadata related to the data stored to the sharded distributed data storage system for storage in the respective first and second addressable virtual shards. The metadata related to the data is stored together at a portion of a corresponding stripe for the data in the second one of the addressable virtual shards. A third one of the addressable virtual shards optionally stores a checksum value related to the data.

Abstract: End-to-end data integrity is provided in parallel computing systems, such as High Performance Computing (HPC) environments. An exemplary method is provided for processing data in a distributed data storage system by obtaining the data and one or more corresponding checksum values from a compute node; and providing the data and the one or more corresponding checksum values to the distributed data storage system for storage. One or more checksum values corresponding to the data can be generated if the one or more checksum values are not received from a compute node. Exemplary processes are provided for copy; slice; merge: and slice and merge functions. The distributed data storage system comprises, for example, one or more Parallel Log-Structured File System (PLFS) storage elements and/or key-value storage elements storing one or more key-value pairs.

Abstract: Techniques are provided for small file aggregation in a parallel computing system. An exemplary method for storing a plurality of files generated by a plurality of processes in a parallel computing system comprises aggregating the plurality of files into a single aggregated file; and generating metadata for the single aggregated file. The metadata comprises an offset and a length of each of the plurality of files in the single aggregated file. The metadata can be used to unpack one or more of the files from the single aggregated file.

Abstract: Transceivers may be used in track circuits. A transceiver may comprise an H-bridge circuit comprising at least four switches. A control unit in communication with the H-bridge circuit may be constructed and arranged to selectively drive the at least four switches to selectively cause the H-bridge circuit to function as a transmitter or a receiver. A power supply terminal in communication with the H-bridge circuit may be constructed and arranged to connect to a power supply. A track interface terminal in communication with the H-bridge circuit may be constructed and arranged to connect to a track interface cable so that the H-bridge circuit is capable of transmitting signals to and/or receiving signals from the track interface cable.

Abstract: Transceivers may be used in track circuits. A transceiver may comprise an H-bridge circuit comprising at least four switches. A control unit in communication with the H-bridge circuit may be constructed and arranged to selectively drive the at least four switches to selectively cause the H-bridge circuit to function as a transmitter or a receiver. A power supply terminal in communication with the H-bridge circuit may be constructed and arranged to connect to a power supply. A track interface terminal in communication with the H-bridge circuit may be constructed and arranged to connect to a track interface cable so that the H-bridge circuit is capable of transmitting signals to and/or receiving signals from the track interface cable.