Research On Integrated Coordination Mechanism Of Data Penetration On Single Chip Processor

On the storage wall problem which refers to the problem that computing speed of the processor does not match the memory access speed,the penetration delay tolerance mechanism has been a new idea to solve this problem in recent years.Although the current simulation experiments have initially proved the effectiveness of the mechanism,there are still some problems in the existing researches:on the one hand,the cognition of the relationship between the penetration data and the on-chip cache is not comprehensive enough;on the other hand,there is a lack of methods to maintain real-time and local penetration data.The penetration delay tolerance mechanism has not played its biggest role because of these problems.Aiming at solving these problems,this paper proposes the freshness theory and the freshness scheduling algorithm by analyzing the relationship between penetration data and permeation cache and studying the migration law of permeation data in the cache.By coordinating the process of data allocation between cache levels,the algorithm can improve the memory access performance of processors.The main work of this paper is as follows:(1)Propose the idea of freshness.Freshness refers to the extent to which penetration data is freshly active in the on-chip cache.The meaning of the fresh activity idea is to combine the temporal locality and spatial locality of the data for the first time,and measure the priority of the data in the on-chip cache.The purpose of the freshness idea is to get the priority that the data will be accessed,and to provide a basis for the distribution of the infiltration data in the on-chip cache.(2)Put forward the freshness cache unit model.The freshness cache unit is improved from the traditional cache unit,and the temporal locality field,spatial locality field and freshness field describing the data block are added to provide hardware basis for the theoretical research and simulation experiment of data allocation in the following part.(3)Propose freshness scheduling algorithm.The main idea of freshness scheduling algorithm is that the overall data is cached on chip to form a real-time dynamic and timely locality situation by judging the timely locality of data according to freshness and to dynamically allocate permeable data in real time.This situation maximizes the retention of useful data in on-chip caching,thus hiding the migration time of data from main memory to caching when the processor makes an access request.(4)Design and implement a simulation tool for data allocation algorithm.Modules such as the processor,caching and main memory are simulated during the design stage in this paper.The freshness scheduling algorithm proposed in this paper is implemented,compared with the random scheduling algorithm,first-in-first-out scheduling algorithm and the recently unused scheduling algorithm.At the experimental stage,the hit rates of the four algorithms are compared,and the experimental results show that the freshness scheduling algorithm has higher hit rate than the traditional scheduling algorithms and the hit rate of the freshness scheduling algorithm is stable.