Energy Optimized Cache Memory Architecture Exploiting Spatial Locality

摘要

Aspects of the present invention provide a “SuperTag” cache that manages cache at three granularities: (i) coarse grain, multi-block “super blocks,” (ii) single cache blocks and (iii) fine grain, fractional block “data segments.” Since contiguous blocks have the same tag address, by tracking multi-block super blocks, the SuperTag cache inherently increases per-block tag space, allowing higher compressibility without incurring high area overheads. To improve compression ratio, the SuperTag cache uses variable-packing compression allowing variable-size compressed blocks without requiring costly compactions. The SuperTag cache also stores data segments dynamically. In addition, the SuperTag cache is able to further improve the compression ratio by co-compressing contiguous blocks. As a result, the Super Tag cache improves energy and performance for memory intensive applications over conventional compressed caches.