Impulse: An Adaptable Memory System

This paper presents the Impulse adaptable memory sys-tem, which allows applications to make efficient use of cache space and bus bandwidth. Impulse has a con-figurable memory controller that allows applications to remap data in the memory system. As a result, applica-tions can control how their data is accessed, organized, and cached. We describe the current design of the Im-pulse architecture, describe the software transformations that will be necessary to make full use of Impulse, and examine in detail the optimizations that Impulse enables: scatter/gather access to sparse data, no-copy page color-ing, and no-copy tile remapping. Results of a simulation study show that Impulse can improve the performance of conjugate gradient by 30%.