INVESTIGATION OF PROCESSES OF LOADING EFFECTS AND RECOVERY OF COMPUTER SYSTEMS PERFORMANCE

Abstract

In the article important issues of the performance of computing systems are considered such as: goals and tasks, a general performance model, fundamental problems in determining performance estimates. The concepts and the most common reasons for a processor and memory leak are identified. The statement of a research problem for processor and memory perform leak as a result of uses web services is formulated, examples of scripts of loading influence are resulted, their characteristic and features of work are directed. An example of recommendations for creating scenarios of the impact on a web service is given. The calculation of the performance evaluations of the impact scenario on the web service is shown, the schedule for the performance of the script is plotted. An important part for study of the performance of computing systems was the development of benchmarks. The main lacks of existing benchmarks include the absence of: load and recovery models, their combined impact, distributed sources of impact. To study the performance of of computing systems in most cases create exposure scenarios. Such scenarios by the type of impact can have different dynamic (velocity) estimates and have different mathematical models. The study of the performance of computer systems using the example of a web service was performed in the operating system Linux Centos 7.0, kernel 3.10, the processor Intel Core i7-3667U, 2.0GHz, with 8 GB of RAM. The software was an apache web server. The load was effected using the httperf utility, performance monitoring was sar, iostat, vmstat. Estimates of the performance of the exposure scenario were verified using mathematical modeling in the SciLab environment using special scripts. Also, the task of researching the performance of computing systems on the example of using web services is formulated, examples of stress loading scripts are given, their characteristics and work features are indicated. Particular importance is given to the model of impact formation. An example of recommendations for creating scenarios of the impact on a web service is given.