Interrupt Model Based Research On Real Time Operating System Performance Evaluation Technology

With the advance of embedded industry, embedded real-time operating system (RTOS) has been widely used and requirement for benchmark on performance of RTOS has been increased year by year. Performance of tasks has been focus of most benchmarks while few benchmarks take a look at the big picture of various aspects of a RTOS and their mutual effects. In this paper we focus on effect of interrupt on RTOS kernel performance benchmarks.First, we analyze and compare three different models of interrupts in case of VxWorks, RTEMS and uC/OSII. Second, we observe the performance of VxWorks, RTEMS, uC/OSII under the condition that interrupts frequency increasing and compare different results given by Rhealstone and Thread-Metric. Based on the results a fixed evaluation method is provided for both Rhealstone and Thread-Metric to meet the requirements of interrupt models. Third, the interrupt disable time is introduced as an indicator of interrupt model and a virtual-machine based method for measuring interrupt disable time is introduced. This method modifies the virtual machine to track runtime behavior of RTOS and log information which is used for calculating interrupt disable time.Results of pre and after fixing Rhealstone and Thread-Metric are compared on Pentium platform. The results indicates that fixed version of evaluation method properly suit the real-world case and fit the analysis of interrupt models. The virtual machine based result also gives evidence that proves the result meet the requirement of interrupt model.