Impact of the Memory Hierarchy on Shared Memory Architectures in Multicore Programming Models

Many and multicore architectures put a big pressure in parallel programming but gives a unique opportunity to propose new programming models that automatically exploit the parallelism of these architectures. Open MP is a very well known standard that exploits parallelism in shared memory architectures. SMPSs has recently been proposed as a task based programming model that exploits the parallelism at the task level and takes into account data dependencies between tasks. However, besides parallelism in the programming, the memory hierarchy impact in many/multi core architectures is a feature of large importance. This paper presents an evaluation of these two programming models with regard to the impact of different levels of the memory hierarchy in the duration of the application. The evaluation is based on trace-files with hardware counters on the execution of a memory intensive benchmark in both programming models.