An embedded key-value storage for learning purpose, which is based on the idea of SSTable / LSM-tree.
- Implement a memtable.
- Implement the write-ahead logging mechanism for the memtable.
- Implement errors detection and recovery process for write-ahead log.
- Write out to a sorted-string segment file when the memtable grows too big, and create a new one.
- Allow searching for keys in sorted-string segment files.
- Implement a merging process for the segment files.
- Build in-memory indexes for every segment files.
- Make the indexes be sparse to save memory by seperating the segment files into blocks and picking the index of the smallest key in each block.
- Compress the blocks before writing to the disk.