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1 How To Really Measure Real-Time Vik Sohal  Ab s tr act In this seminar we will discuss the details of measuring the true real-time performance of any operating system. All modern operating systems have some degree of determinism, identifying this accurately is paramount to determining the viability of a particular OS for a particular application. Designers often attempt to solve real-time problems by speeding up the hardware. We will see how a slow  processor running an efficient RTOS will outperf orm a fast processor running an inefficient RT OS. Our analysis will consist of a combination of empirical and analytical testing applied to a number of measured factors. This process will be used to determine the two most important facets of real-time  performance: Worst Case Task Response Time and Worst Case Interrupt Response Time. Both t hese factors describe the real-time efficiency of an OS. Introduction Our process of measuring the real-time characteristics of an OS will be discussed as answers to the following 3 important questions: 1. What do we need to measure and why? 2. How do we perform our measurements? 3. What do these numbers mean? 1 - What Do We Need To Measure And Why? What Do We Need To Measure? When writing real-time applications, the two most important quantities to know for certain are the  worst- case task 1  response time and the worst-case interrupt response time. Both of these numbers are important as detailed indicators of real-time performance. We will consider the worst-case task response time to be the primary measurement criterion for reasons which will be explained shortly. The centerpiece of all our efforts will be this timeline:  1  We will use the term "task" interchangeably with the terms "process" and "thread"

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