Analysis of the Efficiency of the Simulation Model of Cloud Computing in Case of Multiple Server Failures

Abstract

Currently, the use of distributed (cloud) resources is becoming more and more widespread. Despite the high reliability of equipment used in call centers, failures do occur. And if long-term storage systems have high reliability due to multiple duplication, then the failure of the server on which the task is performed in specialized computing systems (SCS) can correspond to the failure of the entire system. In order to eliminate it, a simulation model of a specialized computing system built in the Simulink (SimEvent) environment, classified in the queuing theory as G/G/n/, is investigated. It is characterized by many input streams with an infinite queue, has two feedbacks, reflecting reprocessing situations in case of a server failure or no solution at the first service attempt. The system architecture is focused on the parallel execution of a certain class of tasks, divided into data-independent sub-tasks. The main criterion for the functioning of such a system is the completion of all received tasks in a time not exceeding the deadline for their implementation. The purpose of the work, the results of which are presented in the article, is to study the reliability of the functioning of such a system for various values of the probability of server failure. Since the performance and efficiency of such a system has already been studied in previous works, the main direction of research will be focused on the impact of server failures on overall productivity and efficiency under various laws of input flows.