Using variance to analyze DBMS performance
Basic statistical indicators of DBMS performance
Median smoothing, with a period of 1 hour.
Additional statistical indicators for analyzing DBMS performance
Performance Variance
For each point t the sample variance is calculated for the input values (sample deviation squared) for the period [ t ; t-60 минут].
Important clarifications on schedules
1. On the performance dispersion graph, there is clearly an inflection point in the graph.
2.Point in time t (60, marked on the graphs with a large yellow dot), in which a break in the dispersion graph appeared (Fig.6) and the break point of the graph of the tangent of the inclined tangent angle (Fig.7) occurred much earlier than a noticeable increase in response time (Fig.1, Fig.2 )
More detailed fragments of graphs
Results, conclusions and plans for the future
The condition of a break in the dispersion graph of the moving DBMS performance value is a sufficient condition for the degradation of DBMS performance.
The break in the dispersion graph of the moving DBMS performance value occurs before an irreversible increase in the DBMS response time during load testing.
To analyze the possibility of using the dispersion graph of the moving average of DBMS performance, additional observations are required under productive load conditions.
Interpretation and deeper analysis of the DBMS performance dispersion graph requires additional experimentation and time.
Perhaps in the course of experiments, it will be possible to obtain new metrics and increase the efficiency of statistical analysis of DBMS performance.