An Improved Method of Task Context Switching in OSEK Operating System.
ABSTRACT Improving real-time is one of the most essential problems in studies of real-time operating system (RTOS). The time of task context switching is an important factor that affects the real-time of RTOS. This paper concentrates on the improvement of task context switching of one kind of RTOS-OSEK operating system. According to different task states, we apply different context switching strategies to reduce the average time of context switching. This method has been successfully implemented and evaluated in our OSEK compatible operating system-SmartOSEK OS.
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ABSTRACT: While the ever-increasing complexity of automotive software systems can be effectively managed through the adoption of a reliable real-time operating system (RTOS), it may incur additional resource usage to a resultant system. Due to the mass production nature of the automotive industry, reducing physical resources used by automotive software is of the utmost importance for cost reduction. OSEK OS is an automotive real-time kernel standard specifically defined to address this issue. Thus, it is very important to develop and exploit kernel mechanisms such that they can achieve minimal resource usage in the OSEK OS implementation. In this paper, we analyze the task subsystem, resource subsystem, application mode and conformance classes of OSEK OS as well as the OSEK Implementation Language (OIL). Based on our analysis, we in turn devise and implement kernel mechanisms to minimize the dynamic memory usage of the OSEK OS implementation. Finally, we show that our mechanisms effectively reduce the memory usage of OSEK OS and applications.Transactions of the Korean Society of Automotive Engineers. 01/2009; 17(3).
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ABSTRACT: In our days microcontrollers are widely used in more and more domains. One of the most important application fields is the automotive one. Because of the great number of microcontrollers included in an automobile and the complexity of tasks they must execute real time operating systems must be implemented. The implementation of the OSEK/VDX operating system on the ADuC703x microcontrollers is described in this paper. ADuC703x are advanced microcontrollers with an ARM7TDMI core, internal RAM and Flash memories and various peripherals on the chip. It was developed targeting the automotive applications. C language was used for implementing the operating system. Hardware dependent sections were written in assembly language as separate modules or included in C ones. The platform Keil ARM was used (compiler, assembler, link editor). The environment which integrated these tools was Keil muVision Integrated Development Environment. No other implementations of the OSEK/VDX operating system on the above mentioned for microcontrollers were found.EUROCON, 2007. The International Conference on "Computer as a Tool"; 10/2007
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ABSTRACT: Nowadays more and more embedded real-time applications use multithreading. The benefits of multithreading include better throughput, improved responsiveness, and ease of development. However, these benefits come with costs and pitfalls which are unacceptable for a typical hard real-time system. These costs are mainly caused by scheduling and context switching between threads. While different scheduling algorithms have been developed to improve the overall system performance, context switching still consumes lot of processor resources and presents a major overhead, especially for hard real-time applications. In this paper, we propose a new approach to improve the overall performance of embedded systems that use multithreading by moving the context switching component of the Real-Time Operating System (RTOS) to the processor hardware itself. This technique leads to savings of processor clock cycles used by context switching, which is a very important resource for a hard real-time embedded systems.Circuits and Systems (MWSCAS), 2011 IEEE 54th International Midwest Symposium on; 01/2011