Different Approaches to Parallelization of Vector Assembly

摘要

Recent developments in computer hardware bring in new opportunities in numerical modelling. Traditional simulation codes run sequentially on computers with a single processing unit, where only one instruction can be processed at any moment in time. The performance of single processing units is reaching the physical limits, given by transmission delays and heat build-up on the silicon chips. The current trend in technology is parallel processing, relying on the simultaneous use of multiple processing units to solve given problem. The efficient utilization of parallel computing resources requires development of new algorithms and techniques allowing to decompose the given task into pieces of work that can be processed simultaneously. This contribution focuses on parallelization of vector assembly operation, which is one of thecritical operations in any finite element software. The aim of presented work is to propose different approaches to parallelization of this operation and to evaluate their efficiency. In this contribution, we focus on shared memory programming model, where individual processes/tasks share a common address space, which they read and write to asynchronously. Open Multi-Processing (OpenMP) and Portable Operating System Interface (POSIX) Threads programming models are used to implement different variants of parallel assembly operations. The efficiency of implemented approaches is evaluated on a selected benchmark problem, comparing computation times and obtained speed-ups.