Research Of Dynamic Memory Management Method On Real-Time Embedded System

With the development of information technology and internet, and the enhancement of intelligence for electronic product, embedded system was more and more popular. The safety and reliability of embedded system were crucial in key field such as spaceflight, industry control and medicine. In order to improve the safety and reliability of data storage in real-time embedded system, research on memory management for embedded system was particularly significant.This thesis proposes a new memory managing arithmetic ---dynamic memory managing adaptive arithmetic,the emphasis is how to reduce memory fragment ,reduce the time of releasing memory, and improve using rate ,and also bring forward new idea and realization. Using different managing methods for small memory block and big memory block in dynamic memory managing adaptive arithmetic, using fixed-size memory allocation method for small memory block can reduce memory fragment effectively, and using actual size memory allocation method for big memory block can raise the utilization rate of memory; the introduction of physical block list make up for the bug of traditional first-fit arithmetic about long time of memory release, and save the time of releasing allocated memory and merging border memory; calculating field record the requested frequency of this size memory ,make memory adjustment get foundation and embody the adaptability sufficiently; The principal makes the remaining memory blocks after Segmentation have precedence over other big memory blocks to be allocated, in this way ,the problem is attributed to a part, and accelerating the speed and reducing internal fragment.Aiming at problem of dynamic memory leak, this thesis proposes a new memory detection method based on dynamic memory managing adaptive arithmetic, and this method can help us focus the exact position where happened memory leak or memory repeating release. This method based on the dynamic memory tracking, because we have recorded all the dynamic memory operation (allocation and release) into a log file, depending on the log we can get all the available information such as the file name, the line number, the operation time and so on, about whether happening memory leak, repeating release or not, and the exact position if memory leak or repeating release have happened.Finally, several simulation tests testify the feasibility and advantage of dynamic memory managing adaptive arithmetic and memory leak detecting method.