Parallel Programming of General-Purpose Programs Using Task-Based Programming Models

The prevalence of multicore processors is bound to drive most kinds of software development towards parallel programming. To limit the difficulty and overhead of parallel software design and maintenance, it is crucial that parallel programming models allow an easy-to-understand, concise and dense representation of parallelism. Parallel programming models such as Cilk++ and Intel TBBs attempt to offer a better, higher-level abstraction for parallel programming than threads and locking synchronization. It is not straightforward, however, to express all patterns of parallelism in these models. Pipelines are an important parallel construct, although difficult to express in Cilk and TBBs in a straightfor- ward way, not without a verbose restructuring of the code. In this paper we demonstrate that pipeline parallelism can be easily and concisely expressed in a Cilk-like language, which we extend with input, output and input/output dependency types on procedure arguments, enforced at runtime by the scheduler. We evaluate our implementation on real applications and show that our Cilk-like scheduler, extended to track and enforce these dependencies has performance comparable to Cilk++.

Service user involvement in drug treatment programs: Barriers to implementation and potential benefits for client recovery

Service user forums have the potential for improving awareness of services, empowering service users and strengthening community partnerships within an inclusive treatment and rehabilitation framework. The research aimed to investigate perspectives about service user involvement in order to inform the development of effective service user forum(s) in west Ireland. A total of 30 interviews with key service providers and 12 interviews with service users were conducted, with interview questions focusing on: (1) awareness of the Service User Support Team and (2) barriers to service user involvement and the development of service user forums in the region. An integrated data collection and thematic analysis was undertaken. Current levels of service user involvement were low, restricted by one-way communication and appeared grounded in user-provider power differentials and stigma relating to drug dependency. Service providers queried the actual terms of reference, capacity and training that would be needed for service user forums to advocate and lobby for service users. The use of existing support groups, creation of internet user forums and rotation of rural meetings were recommended to promote engagement among service users. The research underscores the need for transparency, resources and a framework for good practice that reflects a participatory approach


Read More: http://informahealthcare.com/doi/abs/10.3109/09687637.2012.671860