Abstract-Traditional parallel applications have exploited regular parallelism, based on parallel loops. Only a few applications exploit sections parallelism. With the release of the new OpenMP specification (3.0), this programming model supports tasking. Parallel tasks allow the exploitation of irregular parallelism, but there is a lack of benchmarks exploiting tasks in OpenMP.With the current (and projected) multicore architectures that offer many more alternatives to execute parallel applications than traditional SMP machines, this kind of parallelism is increasingly important. And so, the need to have some set of benchmarks to evaluate it.In this paper, we motivate the need of having such a benchmarks suite, for irregular and/or recursive task parallelism. We present our proposal, the Barcelona OpenMP Tasks Suite (BOTS), with a set of applications exploiting regular and irregular parallelism, based on tasks.We present an overall evaluation of the BOTS benchmarks in an Altix system and we discuss some of the different experiments that can be done with the different compilation and runtime alternatives of the benchmarks.

Tasking in OpenMP 3.0 has been conceived to handle the dynamic generation of unstructured parallelism. New directives have been added allowing the user to identify units of independent work (tasks) and to define points to wait for the completion of tasks (task barriers). In this document we propose extensions to allow the runtime detection of dependencies between generated tasks, broading the range of applications that can benefit from tasking or improving the performance when load balancing or locality are critical issues for performance. The proposed extensions are evaluated on a SGI Altix multiprocessor architecture using a couple of small applications and a prototype runtime system implementation.

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In this paper we describe an implementation overview of Nanos v4: an OpenMP Run Time Library (RTL) based on the nano-threads programming model. Our main goal is to discuss different aspects of the library development focusing on the implementation of a new feature introduced in the last OpenMP release: task support.We compare the performance of our prototype implementation and the workqueuing model available on the Intel compiler with a set of kernel applications.

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