5,000 research outputs found
OpenCL Actors - Adding Data Parallelism to Actor-based Programming with CAF
The actor model of computation has been designed for a seamless support of
concurrency and distribution. However, it remains unspecific about data
parallel program flows, while available processing power of modern many core
hardware such as graphics processing units (GPUs) or coprocessors increases the
relevance of data parallelism for general-purpose computation.
In this work, we introduce OpenCL-enabled actors to the C++ Actor Framework
(CAF). This offers a high level interface for accessing any OpenCL device
without leaving the actor paradigm. The new type of actor is integrated into
the runtime environment of CAF and gives rise to transparent message passing in
distributed systems on heterogeneous hardware. Following the actor logic in
CAF, OpenCL kernels can be composed while encapsulated in C++ actors, hence
operate in a multi-stage fashion on data resident at the GPU. Developers are
thus enabled to build complex data parallel programs from primitives without
leaving the actor paradigm, nor sacrificing performance. Our evaluations on
commodity GPUs, an Nvidia TESLA, and an Intel PHI reveal the expected linear
scaling behavior when offloading larger workloads. For sub-second duties, the
efficiency of offloading was found to largely differ between devices. Moreover,
our findings indicate a negligible overhead over programming with the native
OpenCL API.Comment: 28 page
Concurrent Lexicalized Dependency Parsing: A Behavioral View on ParseTalk Events
The behavioral specification of an object-oriented grammar model is
considered. The model is based on full lexicalization, head-orientation via
valency constraints and dependency relations, inheritance as a means for
non-redundant lexicon specification, and concurrency of computation. The
computation model relies upon the actor paradigm, with concurrency entering
through asynchronous message passing between actors. In particular, we here
elaborate on principles of how the global behavior of a lexically distributed
grammar and its corresponding parser can be specified in terms of event type
networks and event networks, resp.Comment: 68kB, 5pages Postscrip
Modelling Reactive Multimedia: Design and Authoring
Multimedia document authoring is a multifaceted activity, and authoring tools tend to concentrate on a restricted set of the activities involved in the creation of a multimedia artifact. In particular, a distinction may be drawn between the design and the implementation of a multimedia artifact.
This paper presents a comparison of three different authoring paradigms, based on the common case study of a simple interactive animation. We present details of its implementation using the three different authoring tools, MCF, Fran and SMIL 2.0, and we discuss the conclusions that may be drawn from our comparison of the three approaches
RELEASE: A High-level Paradigm for Reliable Large-scale Server Software
Erlang is a functional language with a much-emulated model for building reliable distributed systems. This paper outlines the RELEASE project, and describes the progress in the rst six months. The project aim is to scale the Erlang's radical concurrency-oriented programming paradigm to build reliable general-purpose software, such as server-based systems, on massively parallel machines. Currently Erlang has inherently scalable computation and reliability models, but in practice scalability is constrained by aspects of the language and virtual machine. We are working at three levels to address these challenges: evolving the Erlang virtual machine so that it can work effectively on large scale multicore systems; evolving the language to Scalable Distributed (SD) Erlang; developing a scalable Erlang infrastructure to integrate multiple, heterogeneous clusters. We are also developing state of the art tools that allow programmers to understand the behaviour of massively parallel SD Erlang programs. We will demonstrate the e ectiveness of the RELEASE approach using demonstrators and two large case studies on a Blue Gene
Efficient and Reasonable Object-Oriented Concurrency
Making threaded programs safe and easy to reason about is one of the chief
difficulties in modern programming. This work provides an efficient execution
model for SCOOP, a concurrency approach that provides not only data race
freedom but also pre/postcondition reasoning guarantees between threads. The
extensions we propose influence both the underlying semantics to increase the
amount of concurrent execution that is possible, exclude certain classes of
deadlocks, and enable greater performance. These extensions are used as the
basis an efficient runtime and optimization pass that improve performance 15x
over a baseline implementation. This new implementation of SCOOP is also 2x
faster than other well-known safe concurrent languages. The measurements are
based on both coordination-intensive and data-manipulation-intensive benchmarks
designed to offer a mixture of workloads.Comment: Proceedings of the 10th Joint Meeting of the European Software
Engineering Conference and the ACM SIGSOFT Symposium on the Foundations of
Software Engineering (ESEC/FSE '15). ACM, 201
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