Improving memory performance of embedded Java applications by dynamic layout modifications

Summary form only given. Unlike desktop systems, embedded systems use different user interface technologies; have significantly smaller form factors; use a wide variety of processors; and have very tight constraints on power/energy consumption, user response time, and physical space. With its platform independence and secure execution environment, Java is fast becoming the language of choice for programming embedded systems. In order to extend its use to array based applications from embedded image and video processing, Java programmers need to employ several optimizations. Unfortunately, due to its precise exception mechanism and bytecode distribution form, it is not generally possible to use classical loop based optimization techniques for array based embedded Java applications. Observing this, this paper proposes a dynamic memory layout optimization strategy for Java applications. The strategy is based on observing the cache behavior dynamically and transforming memory layouts of arrays, when necessary, during the course of execution. This is in contrast to many previously proposed memory layout optimization strategies, which are static in nature (i.e., they are applied at compile time). Our results indicate large performance improvements on a suite of seven array based applications.