Supporting Elasticity in OpenMP Applications

Elasticity can be seen as the ability of a system to increase or decrease the computing resources allocated in a dynamic and on demand way. In order to explore this feature, several works addressed the development of frameworks and platforms focusing the construction of elastic parallel and distributed applications for IaaS clouds. However, none of these works addressed the exploration of elasticity in multithreaded applications. In this paper, we propose a mechanism to provide elasticity support for OpenMP applications, making possible the dynamic provisioning of cloud resources taking into account the program structure and runtime requirements. In our proposal, the OpenMP directives were modified to support the dynamic adjustment of resources and a set of routines were included to the user-level library in order to enable the configuration of the the elastic execution. Dynamic memory allocation support was also included in elastic OpenMP library. We also present the architecture and implementation of the proposed mechanism. The experiments validate our approach and show some possibilities to use the elastic OpenMP.