METAL: Caching Multi-level Indexes in Domain-Specific Architectures

State-of-the-art domain specific architectures (DSAs) work with sparse data, and need hardware support for index data-structures [31, 43, 57, 61]. Indexes are more space-efficient for sparse-data, and reduce DRAM bandwidth, if data reuse can be managed. However, indexes exhibit dynamic accesses, chase pointers, and need to walk-and-search. This inflates the working set and thrashes the cache. We observe that the cache organization itself is responsible for this behavior.