Proofs of Soundness and Strong Normalization for Linear Memory Types

Efficient low-level systems need more control over memory than safe high-level languages usually provide. As a result, run-time systems are typically written in unsafe languages such as C. This report describes an abstract machine designed to give type-safe code more control over memory. It includes complete definitions and proofs

Automatic Detection of Performance Anomalies in Task-Parallel Programs

To efficiently exploit the resources of new many-core architectures, integrating dozens or even hundreds of cores per chip, parallel programming models have evolved to expose massive amounts of parallelism, often in the form of fine-grained tasks. Task-parallel languages, such as OpenStream, X10, Habanero Java and C or StarSs, simplify the development of applications for new architectures, but tuning task-parallel applications remains a major challenge. Performance bottlenecks can occur at any level of the implementation, from the algorithmic level (e.g., lack of parallelism or over-synchronization), to interactions with the operating and runtime systems (e.g., data placement on NUMA architectures), to inefficient use of the hardware (e.g., frequent cache misses or misaligned memory accesses); detecting such issues and determining the exact cause is a difficult task. In previous work, we developed Aftermath, an interactive tool for trace-based performance analysis and debugging of task-parallel programs and run-time systems. In contrast to other trace-based analysis tools, such as Paraver or Vampir, Aftermath offers native support for tasks, i.e., visualization, statistics and analysis tools adapted for performance debugging at task granularity. However, the tool currently does not provide support for the automatic detection of performance bottlenecks and it is up to the user to investigate the relevant aspects of program execution by focusing the inspection on specific slices of a trace file. In this paper, we present ongoing work on two extensions that guide the user through this process.Comment: Presented at 1st Workshop on Resource Awareness and Adaptivity in Multi-Core Computing (Racing 2014) (arXiv:1405.2281

A Case Study of Workflow and Version Control for Regeneration of Multimedia Systems

The technologies involved in the creation of multimedia content are still in evolution. One-off generation of systems is well-developed as a process and often follows the model of making a film. Many modern applications are more complicated than film productions processes in that they must be regenerated time and time again, as a repeated production process, often by passing the materials through computational processes, and as well, they must be supplied in forms suitable for a variety of delivery media, such as books, web page or CD-ROM run-time systems. To create efficiencies in the production process of revisable multi-media systems it is necessary to define processes for the management of content, control of content revision, and regeneration with workflow control of these processes. A model for managing the regeneration of Multimedia Run-time Systems (MRS) is presented here as consisting of a revision control strategy for managing primary resources. Regeneration processes are required that move data from one process to the next incorporating derived resources on the way, and ultimately producing run-time resources. As well, workflow control process to regulate and maintain the integrity of the regeneration process is needed. A case study of one approach to tackling these problems which uses reference materials for second language learning is presented. This MRS, known as the English to Basque Learning Environment (EBLE), consists of a reference library of three books and concomitant sound files for second language learning of Basque. The books are a grammar book and two dictionaries which had to be welded together seamlessly for a run-time system but each is preserved seperately and managed as independent documents for maintenance and revision. As well, the examples of Basque and English in the grammar book are recorded by native speakers and the sound files linked into the software environment with immediate access to the user. A model for managing Multimedia Run-time Systems (MRS) is presented as consisting of a revision control strategy for managing primary resources; regeneration processes that move data from one process to the next incorporating derivative resources on the way, and ultimately producing run-time resources; and a workflow control process to regulate and maintain the integrity of the regeneration processes.Hosted by the Scholarly Text and Imaging Service (SETIS), the University of Sydney Library, and the Research Institute for Humanities and Social Sciences (RIHSS), the University of Sydney

A Case Study of Workflow and Version Control for Regeneration of Multimedia Systems

The technologies involved in the creation of multimedia content are still in evolution. One-off generation of systems is well-developed as a process and often follows the model of making a film. Many modern applications are more complicated than film productions processes in that they must be regenerated time and time again, as a repeated production process, often by passing the materials through computational processes, and as well, they must be supplied in forms suitable for a variety of delivery media, such as books, web page or CD-ROM run-time systems. To create efficiencies in the production process of revisable multi-media systems it is necessary to define processes for the management of content, control of content revision, and regeneration with workflow control of these processes. A model for managing the regeneration of Multimedia Run-time Systems (MRS) is presented here as consisting of a revision control strategy for managing primary resources. Regeneration processes are required that move data from one process to the next incorporating derived resources on the way, and ultimately producing run-time resources. As well, workflow control process to regulate and maintain the integrity of the regeneration process is needed. A case study of one approach to tackling these problems which uses reference materials for second language learning is presented. This MRS, known as the English to Basque Learning Environment (EBLE), consists of a reference library of three books and concomitant sound files for second language learning of Basque. The books are a grammar book and two dictionaries which had to be welded together seamlessly for a run-time system but each is preserved seperately and managed as independent documents for maintenance and revision. As well, the examples of Basque and English in the grammar book are recorded by native speakers and the sound files linked into the software environment with immediate access to the user. A model for managing Multimedia Run-time Systems (MRS) is presented as consisting of a revision control strategy for managing primary resources; regeneration processes that move data from one process to the next incorporating derivative resources on the way, and ultimately producing run-time resources; and a workflow control process to regulate and maintain the integrity of the regeneration processes.Hosted by the Scholarly Text and Imaging Service (SETIS), the University of Sydney Library, and the Research Institute for Humanities and Social Sciences (RIHSS), the University of Sydney

Language run-time systems:An overview

The proliferation of high-level programming languages with advanced language features and the need for portability across increasingly heterogeneous and hierarchical architectures require a sophisticated run-time system to manage program execution and available resources. Additional benefits include isolated execution of untrusted code and the potential for dynamic optimisation, among others. This paper provides a high-level overview of language run-time systems with a focus on execution models, support for concurrency and parallelism, memory management, and communication, whilst briefly mentioning synchronisation, monitoring, and adaptive policy control. Two alternative approaches to run-time system design are presented and several challenges for future research are outlined. References to both seminal and recent work are provided

Model Variations and Automated Refinement of Domain-Specific Modeling Languages for Robot-Motion Control

This paper presents an approach to handling frequent variations of modeling languages and models. The approach is based on Domain-Specific Modeling and linking of modeling tools with adaptive Run-Time Systems. The applicability of our solution is illustrated on an example of domain-specific languages for robot control. Special attention was given to the following problems: 1) model-level debugging; 2) performing fast transformation of models to native code for various hardware platforms and operating systems; and 3) specification of views and view-based generation of applications for validation of meta-models, models, and generated code. The feedback for automated refinement of models and meta-models is provided by a custom adaptive Run-Time System. For the purpose of synchronizing models, meta-models, and the target Run-Time System, we introduce action reports, which allow model-level debugging. In order to simplify handling of frequent model variations, we have introduced the linguistic concept of a modifier

Formal Properties of Linear Memory Types

Efficient low-level systems need more control over memory than safe high-level languages usually provide. As a result, run-time systems are typically written in unsafe languages such as C. This report describes an abstract machine designed to give type-safe code more control over memory. It includes complete definitions and proofs of preservation, progress, strong normalization, erasure, and translation correctness