Adapting application execution in CMPs using helper threads

In parallel to the changes in both the architecture domain–the move toward chip multiprocessors (CMPs)–and the application domain–the move toward increasingly data-intensive workloads–issues such as performance, energy efficiency and CPU availability are becoming increasingly critical. The CPU availability can change dynamically due to several reasons such as thermal overload, increase in transient errors, or operating system scheduling. An important question in this context is how to adapt, in a CMP, the execution of a given application to CPU availability change at runtime. Our paper studies this problem, targeting the energy-delay product (EDP) as the main metric to optimize. We first discuss that, in adapting the application execution to the varying CPU availability, one needs to consider the number of CPUs to use, the number of application threads to accommodate and the voltage/frequency levels to employ (if the CMP has this capability). We then propose to use helper threads to adapt the application execution to CPU availability change in general with the goal of minimizing the EDP. The helper thread runs parallel to the application execution threads and tries to determine the ideal number of CPUs, threads and voltage/frequency levels to employ at any given point in execution. We illustrate this idea using four applications (Fast Fourier Transform, MultiGrid, LU decomposition and Conjugate Gradient) under different execution scenarios. The results collected through our experiments are very promising and indicate that significant EDP reductions are possible using helper threads. For example, we achieved up to 66.3%, 83.3%, 91.2%, and 94.2% savings in EDP when adjusting all the parameters properly in applications FFT, MG, LU, and CG, respectively. We also discuss how our approach can be extended to address multi-programmed workloads.     

事件驱动编程中对Browse的控制

从数据库管理系统设计中数据个性模块的顺序驱动和谐和事件驱动编程的比较入手,提出了事件驱编程中控制Browse需要考虑的几个问题,并具体分析了每个问题的解决办法。     

云计算数据安全

提出了一种可以同时解决云环境下数据的隐私性、可用性和完整性安全挑战的方法。综述了当前具有代表性的数据安全技术,着重分析了它们的功能单一性缺陷,并通过改进使之更加完善。提出了使用第三方审计不仅可以批量验证云租户数据的完整性,还可以构建云环境的可信链以及保障云租户数据隐私性的新思路。     

基于无双线性对的可信云数据完整性验证方案

针对云审计中第三方审计机构（TPA）可能存在的恶意欺骗行为,提出一种无双线性对的、能够正确检查TPA行为的可信云审计方案。首先,利用伪随机比特生成器生成随机挑战信息,以保证TPA生成挑战信息可靠;其次,在证据生成过程中增加哈希值,从而有效保护用户数据隐私;然后,在证据验证过程中,增加用户和TPA结果的交互过程,根据这个结果检查数据完整性,并判断TPA是否如实完成审计请求;最后,扩展该方案以实现多项数据的批量审计。安全分析表明,所提方案能够抵抗替换攻击和伪造攻击,且能保护数据隐私。相比基于Merkle哈希树的无双线性对（MHT-WiBPA）审计方案,所提方案的验证证据时间接近,而标签生成时间降低约49.96%。效能分析表明,所提方案在保证审计结果可信的前提下,实现了更低的计算开销和通信开销。     

Data protection aspects in an integrated hospital information system

Data protection aspects in a large, integrated Hospital Information System are described. A special feature in this case is the interaction between the operating system BOS and a large number of application subsystems. (Both system and application software has been developed in-house by BAZIS). Integration aspects are shown to contribute to data protection. The main topic in the present article is access control; however, several measures with regard to accuracy, consistency and availability of the information (data integrity) will also be mentioned.     

Contingency planning in the banking community

This article deals with computer contingency planning in the banking community. Its focus is on Federal regulatory banking agencies and various banking associations and their parts in influencing banks to develop contingency plans. Examples of specific banks' contingency plans are presented.     

Information as a corporate asset

The author explains the need for and necessity of information for running a complex multinational company like Philips. He gives a short overview of the organization and structure of Philips, employing almost 400,000 people, and its world-wide activities. He deals with specific aspects and problems regarding the production, storage and distribution of a large range of Philips products, i.e., how this huge task was tackled in the early EDP days, and what difficulties and troubles had to be overcome. Gradually a new generation of managers has developed who are able to handle the possibilities of computers and automated information systems.However, the multinational Philips covers thousands of separate units which cannot operate on their own. For business-information exchange they have to communicate in a well-defined language based on stadardized data elements. Data-bases, in the future interconnected by a world-wide communications network, contain data that represent valuable and indispensible information for the Philips company: a real corporate asset.With some reserve the writer dares to make predictions about the future of automation, yet mentions some clear trends and draws interesting conclusions.     

Selection process for security packages

The primary goal of this paper is to provide a simplified process which can be used for the selection of a security package. The material has been made specifically non-technical so that it can be used by persons with little technical background. The process is based on a formula, which, after application, results in a single measure by weighing the security features in a package against the requirements as set by management.     

会计电算化环境下企业内部控制制度创新研究

会计电算化的出现和运用,使会计计算技术由简单的数值计算发展到全面数值核算,人工智能会计管理信息系时代已经到来。随着会计电算化快速发展。在给企业带来巨大效益的同时,也给企业内部控制带来新的问题。会计电算化要求并需要企业内部控制制度创新。开展会计电算化环境下企业内部控制制度创新研究,对于实现企业管理的制度化,规范化,科学化具有重要的意义。     

浅议基本建设项目审计中应注意的问题

对审计主体、审计客体、审计本质等基本建设项目审计的相关概念进行了介绍,阐述了基本建设项目审计的现状,并提出了审计人员在审计中要注意的几个重点,以提高审计质量,从而改善投资管理,提高投资效益.