Transaction processing in distributed active real-time database systems

An active real-time database system (ARTDBS) is designed to provide timely response to the critical situations that are defined on database states. Although a number of studies have already addressed various issues in ARTDBSs, little attention has been paid to scheduling transactions in a distributed ARTDBS environment. In this paper, 2 we describe a detailed performance model of a distributed ARTDBS and investigate various performance issues in time-cognizant transaction processing in ARTDBSs. The experiments conducted evaluate the performance under various types of active workload and different distributed transaction-processing architectures. The performance metric used in the evaluations is the fraction of transactions that violate their timing constraints. We also describe and evaluate a nested transaction execution scheme that improves the real-time performance under high levels of active workload. © 1998 Elsevier Science Inc. All rights reserved

SOA-RTDBS: A service oriented architecture (SOA) supporting real time database systems

With the increase of complexity in Real-time Database Systems (RTDBS), the amount of data that needs to be managed has also increased. Adoption of a RTDBS as a tightly integrated part of the SOA development process can give significant benefits with respect to data management. However, the variability of data management requirements in different systems, and its heterogeneity may require a distinct database configuration. We addressed the challenges that face RTDB managers who intend to adopt RTDBS in SOA market; we also introduce a service oriented approach to RTDBS analytics and describe how this is used to measure and to monitor the security system. A SOA approach for generating RTDBS configurations suitable for resource-constrained real-time systems using Service Oriented Architecture tools to assist developers with design and analysis of services of developed or new systems was also explored

Dynamic power management: from portable devices to high performance computing

Electronic applications are nowadays converging under the umbrella of the cloud computing vision. The future ecosystem of information and communication technology is going to integrate clouds of portable clients and embedded devices exchanging information, through the internet layer, with processing clusters of servers, data-centers and high performance computing systems. Even thus the whole society is waiting to embrace this revolution, there is a backside of the story. Portable devices require battery to work far from the power plugs and their storage capacity does not scale as the increasing power requirement does. At the other end processing clusters, such as data-centers and server farms, are build upon the integration of thousands multiprocessors. For each of them during the last decade the technology scaling has produced a dramatic increase in power density with significant spatial and temporal variability. This leads to power and temperature hot-spots, which may cause non-uniform ageing and accelerated chip failure. Nonetheless all the heat removed from the silicon translates in high cooling costs. Moreover trend in ICT carbon footprint shows that run-time power consumption of the all spectrum of devices accounts for a significant slice of entire world carbon emissions. This thesis work embrace the full ICT ecosystem and dynamic power consumption concerns by describing a set of new and promising system levels resource management techniques to reduce the power consumption and related issues for two corner cases: Mobile Devices and High Performance Computing