Key-value stores with optimized merge policies and optimized LSM-tree structures

摘要

Embodiments of the invention utilize an improved LSM-tree-based key-value approach to strike the optimal balance between the costs of updates and lookups and storage space. The improved approach involves use of a new merge policy that removes merge operations from all but the largest levels of LSM-tree. In addition, the improved approach may include an improved LSM-tree that allows separate control over the frequency of merge operations for the largest level and for all other levels. By adjusting various parameters, such as the storage capacity of the largest level, the storage capacity of the other smaller levels, and/or the size ratio between adjacent levels in the improved LSM-tree, the improved LSM-tree-based key-value approach may maximize throughput for a particular workload.