TIMELINESS ASSESSMENT FOR IMPLEMENTATION OF THE CRITICAL REQUESTS IN TWO-LEVEL CLUSTERS

• Main Authors: A. V. Bogatyrev, V. A. Bogatyrev, S. V. Bogatyryev
• Format: Article
• Language: English
• Published: Saint Petersburg National Research University of Information Technologies, Mechanics and Optics (ITMO University) 2014-03-01
• Series: Naučno-tehničeskij Vestnik Informacionnyh Tehnologij, Mehaniki i Optiki
• Subjects: timeliness; reliability; real-time; queries; cluster
• Online Access: http://ntv.ifmo.ru/file/article/9419.pdf

The paper deals with probability evaluation for timely service of requests in real-time systems at the time less than permitted limit in a two-level cluster where each incoming request is served first, in one of the bottom-level nodes and then in one of the top-level nodes. To determine the probability that the stay of queries in a two-level cluster system is less than the permissible value, we break this time at equal intervals. We define the probability of not exceeding the delay on the first level, different number of intervals, calculating the probability that a delay on the second level will not exceed the remaining float for valid residence time of the query in the system. The proposed assessment can be used in the comprehensive reliability estimation of computational processes in two-level systems of cluster architecture, operating in real time.