Use of hybrid approaches that symbiotically combine analysis and measurements for deriving high-confidence tight service-time bounds (STBs) in real-time distributed computing (RTDC) applications represents a promising...
详细信息
ISBN:
(纸本)9783642042836
Use of hybrid approaches that symbiotically combine analysis and measurements for deriving high-confidence tight service-time bounds (STBs) in real-time distributed computing (RTDC) applications represents a promising research area. A hybrid approach of this type was recently proposed for deriving STBs for methods in object-oriented RTDC applications. The approach combines analytical and measurement-based techniques to find a tight STB falling between the maximum measured service time and an analytically derived loose STB. A curve-fitting technique is applied to relate the measured data to the loose bound and also enables the estimation of the probability of the chosen STB not being exceeded at run time. Experimental research for checking the feasibility and potential problems of this type of hybrid approaches has been scarce. In this paper we report on the results of one case study aimed for validating the curve-fitting based hybrid approach mentioned above. The RTDC application dealt with in this experimental work is a relatively simple distributed video streaming application, called Televideo.
Object-oriented analysis and design methodologies have become popular in development of non-real-time business data processing applications. However, conventional object-oriented techniques have had minimal impacts on...
详细信息
ISBN:
(纸本)0818684321
Object-oriented analysis and design methodologies have become popular in development of non-real-time business data processing applications. However, conventional object-oriented techniques have had minimal impacts on development of real-time applications mainly because these techniques do not explicitly address key characteristics of real-time systems, in particular, timing requirements. The time-triggeredmessage-triggered Object (TMO) structuring is in our view the most natural extension of the object-oriented design and implementation techniques which allows the system designer to explicitly specify timing characteristics of data and function components of an object. To facilitate TMO-based design of real-time systems in the most cost-effective manner, it is essential to provide execution support mechanisms in well-established commercial software/hardware platforms compliant with industry standards. In this paper, we present an implementation model for TMO support mechanisms in CORBA-compliant commercial-off-the-self (COTS) platforms. We first introduce a natural and simple mapping between TMO's and CORBA objects. Then, we identify the services to be provided by the TMO support subsystem and an efficient way these services should be implemented. The rest of the paper discusses an implementation of the proposed model realized on top of the Windows NT operating system and the Orbix object request).
暂无评论