João Lourenço

Transactional memory (TM) is an increasingly popular technique for synchronising threads in multi-threaded programs. To address both correctness and performance-related issues of TM programs, one needs to monitor and analyse their execution. However, monitoring concurrent programs (including TM programs) may have a non-negligible impact on their behaviour, which may hamper the objectives of the intended analysis. In this paper, we propose several approaches for monitoring TM programs and study their impact on the behaviour of the monitored programs. The considered approaches range from specialised lightweight monitoring to generic heavyweight monitoring. The implemented monitoring tools are publicly available to the scientific community, and the implementation techniques used for lightweight monitoring of TM programs may be used as an inspiration for developing other specialised lightweight monitors.

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The recent developments in virtualization change completely the panorama of the Hardware/OS deployment. New bottlenecks arise in the deployment of application stacks, where IT industry will spend most of the time to assure automation. VIRTU tool aims at managing, configuring and testing distributed ground applications of space systems on a virtualized environment, based on open tools and cross virtualization support. This tool is a spin-off of previous activities performed by the European Space Operations Center (ESOC) and thus it covers the original needs from the ground data systems infrastructure division of the European Space Agency. VIRTU is a testing oriented solution. Its ability to group several virtual machines in an assembly provides the means to easily deploy a full testing infrastructure, including the client/server relationships. The possibility of making on-demand request of the testing infrastructure will provide some infrastructure optimizations, specially having in mind that ESA maintains Ground Control software of various missions, and each mission cam potentially have a different set of System baselines and last up to 15 years. The matrix array of supported system combinations is therefore enormous and any improvement on the process provides substantial benefits to ESA, by reducing the effort and schedule of each maintenance activity. The ESOC's case study focuses on the development and validation activities of infrastructure or mission Ground Systems solutions. The Ground Systems solutions are typically composed of distributed systems that could take advantage of virtualized environments for testing purposes. Virtualization is used as way to optimize maintenance for tasks such as testing new releases and patches, test different system's configurations and replicate tests. The main benefits identified are related to deployment test environment and the possibility to have on-demand infrastructure.