Adaptive prefetching for multimedia applications in embedded systems
Hassan Sbeyti, Smaïl Niar, Lieven Eeckhout · 2004
This paper presents a new and simple prefetching mechanism to improve the memory performance of multimedia applications. This method adapts the memory access mechanism to the access patterns as observed in the application. By doing so, performance is increased, the available resources are better utilized and energy consumption is reduced. Using our prefetch method, we are able to get up to 5.5 % IPC improvement, more than 50 % cache miss reduction, and up to 4.5 % energy reduction. Our mechanism results in better performance for a 2KB data cache than is achievable with an 8KB data cache (without prefetching) for StrongArm SA1110 and Xscale-like processor configurations. This mechanism requires limited hardware resources and generates little additional external bus transfers. This makes this adaptive prefetching well suited for embedded microprocessor systems 1. Memory access behavior for the MPEG4 Video sequence compression/decompression algorithms like MPEG4 are used in many applications because of their efficiency in supporting different compression bit rates (5Kbits/s-5Mbits/s), their enhanced error resilience/robustness, their content-based interactivity and scalability which make them applicable in mobile systems. On the other hand, these algorithms require a high computational processing power and memory bandwidth. The high memory bandwidth requirements do not only affect the real-time behavior of such applications but also their energy consumption. In this paper, we analyze and show how to exploit the memory behavior of MPEG4 applications on an embedded system. We used the SimpleScalar Tool Set [1] to profile the MPEG4 application at run time. The following video sequences are used: foreman, news, and container with two different