Bulba S. Models and methods of processing transactions of composite applications in heterogeneous distributed computer systems

The dissertation is devoted to solving the problem of resource allocation between composite applications in distributed cloud environments on the basis of mathematical model development (mathematical models and methods) of transaction processing of a composite application. The aim of the work is to increase the efficiency of the use of distributed computer systems resources, based on the development of new and improved existing models and methods of handling the transactions of composite applications. In the dissertation the mathematical model of the process of distribution of resources between composite applications in a distributed cloud environment was proposed for the first time, which, in contrast to the existing ones, takes into account time windows by introducing virtual time during the considered time interval of information processing, allowing to take into account periodically arising restrictions on availability of certain resources. The criterion for assessing the quality of distribution of distributed, cloud-based resources is improved, which, unlike existing ones, uses the utilization rate of resources, and allowed to increase the balance of load when executing transactions of composite applications. Has further developed the method of planning the implementation of transactions of composite applications due to the joint use of greedy, clustering and ant methods of optimization, which reduced the time to execute the optimal plan of transactions in comparison with existing methods up to 8%.