Cascade Mapping
Kefei Wang, Feng Chen · 2018
Flash-based key-value caching plays an important role in Internet services. Compared to in-memory key-value caches, flash-based key-value caches can provide a 10 to 100 times larger cache space, allowing to accommodate more data for a higher hit ratio. However, the current design relies on a simple hash-based indexing structure, which maintains the entire mapping table in DRAM memory. As the cache capacity continues to grow, such an "all-in-memory" approach raises concerns on cost, power, and scalability.