Visual Evaluation Of Sql Plan Cache Algorithms

Caching optimized query plans reduces the time spent optimizing SQL queries at the cost of increased memory consumption. Different cache eviction strategies, such as LRU(-K) or GD(F) S exist that aim at increasing the cache hit ratio or reducing the overall cost of cache misses. A comprehensive study on how different workloads and tuning parameters influence these strategies does not yet publicly exist. We propose a tool that enables both such research as well as performance tuning for DBAs by visualizing the effects of changed parameters in real time.