PVM (the current version 3.4) as well as many current MPI implementations force application programmers to use active polling (also known as busy waiting) in larger parallel programs. This serious problem is related to thread-unsafety of these communication libraries. While the MPI specification is very careful in this respect, the implementations are not.… (More)
A demand-driven parallelization of the ray tracing algorithm is presented. Correctness and optimality of a perfect load balancing algorithm for image space subdivision are proved and its exact message complexity is given. An integration of antialiasing into the load balancing algorithm is proposed. A distributed object database allows rendering of complex… (More)
The paper investigates a version of the resource allocation problem arising in the wireless networking, namely in the OVSF code reallocation process. In this setting a complete binary tree of a given height n is considered, together with a sequence of requests which have to be served in an online manner. The requests are of two types: an insertion request… (More)
Simulation of global illumination in 3D scenes is a compu-tationally expensive task. One of the goals of the project HiQoS (High Performance Multimedia Services with Quality of Service Guarantees) was to develop and test a prototype of an e-commerce system which simulates realistic lighting of large scenes on high performance parallel computers. The system,… (More)
This paper investigates assignment strategies (load balancing algorithms) for process farms which solve the problem of online placement of a constant number of independent tasks with given, but unknown, time complexities onto a homogeneous network of processors with a given latency. Results for the chunking and factoring assignment strategies are summarised… (More)
All papers were reviewed and selected by international program committee.
Finding a schedule with minimal makespan for a finite number of independent tasks on a homogeneous network of processors is an NP-hard problem if durations of all tasks are known. With only partial a-priori knowledge of tasks' time durations, it makes sense to look for on-line algorithms which guarantee short makespans in terms of small competitive ratios.… (More)
Theoretical models are difficult to apply for the analysis of practical message passing systems used today. We propose a model which can be used for such an analysis. Our framework for message passing is in many ways similar to the framework for transactional database systems. The abstract message passing system is defined in our framework independently of… (More)