  Maintaining multiple versions of data is popular in key-value stores since it
increases concurrency and improves performance. However, designing a
multi-version key-value store entails several challenges, such as additional
capacity for storing extra versions and an indexing mechanism for mapping
versions of a key to their values. We present SkimpyFTL, a FTL-integrated
multi-version key-value store that exploits the remap-on-write property of
flash-based SSDs for multi-versioning and provides a tradeoff between memory
capacity and lookup latency for indexing.
