Patterns for Parallel Software Design

3.1. 3.1 Parallel Pipes and Filters

The Parallel Pipes and Filters pattern extends the original Pipes and Filters pattern [POSA1] [Sha95] [SG96] with aspects of functional parallelism. Each parallel component simultaneously performs a different step of the computation, following a precise order of operations on ordered data that is passed from one computation stage to another as a flow through the whole structure [OR98]. Functional parallelism is the form of parallelism that involves problems whose computation can be described in terms of a series of simultaneous time-step ordered operations, on a series of ordered values or data, with predictable organization and interdependencies. As each step represents a change of the input value or effect over time, a high amount of communication between components in the solution (in the form of a flow) should be considered. Conceptually, a single data value or transformation is performed repeatedly [CG88] [Fos94] [Pan96] [OR98].

3.1.1. Example: Graphics Rendering

In image processing, graphics rendering is a jargon phrase that has come to mean 'the collection of operations necessary to project a view of an object or a scene onto a view surface'. In common applications for the film and video industry, rendering a special effect scene of ten seconds using a standard resolution of 2048 × 1536 pixels takes up to 130 hours of processing time when using the C programming language on a single high-end Macintosh or PC platform [HPCN98]. The input ...