Compare LevelDB vs. TerarkDB

LevelDB is a high-performance key-value storage library developed by Google, designed to maintain an ordered mapping between string keys and string values. The keys and values are treated as arbitrary byte arrays, and the stored data is organized in a sorted manner based on the keys. Users have the option to supply a custom comparison function to modify the default sorting behavior. The library allows for multiple changes to be grouped into a single atomic batch, ensuring data integrity during updates. Additionally, users can create a temporary snapshot for a consistent view of the data at any given moment. The library supports both forward and backward iteration through the stored data, enhancing flexibility during data access. Data is automatically compressed using the Snappy compression algorithm to optimize storage efficiency. Moreover, interactions with the external environment, such as file system operations, are managed through a virtual interface, giving users the ability to customize how the library interacts with the operating system. In practical applications, we utilize a database containing one million entries, where each entry consists of a 16-byte key and a 100-byte value. Notably, the values used in benchmarking compress to approximately half of their original size, allowing for significant space savings. We provide detailed performance metrics for sequential reads in both forward and reverse directions, as well as the effectiveness of random lookups, to showcase the library's capabilities. This comprehensive performance analysis aids developers in understanding how to optimize their use of LevelDB in various applications.

TerarkDB serves as a flagship offering from Terark, functioning as a specialized distribution of RocksDB that is enhanced by proprietary Terark algorithms. These algorithms enable TerarkDB to achieve significantly greater data storage capacity and retrieval speeds compared to the standard RocksDB, boasting performance metrics of over three times the data capacity and more than ten times the access speed on identical hardware configurations. Additionally, TerarkDB maintains full binary compatibility with the official RocksDB, ensuring seamless integration for users. By forking RocksDB, we have implemented targeted modifications to optimize it for our algorithms, which can be found as a submodule named rocksdb. Importantly, these adaptations preserve all existing RocksDB APIs and do not introduce any additional dependencies; for instance, TerarkDB operates independently of TerarkZipTable, ensuring that it functions identically to the official RocksDB without any modifications required in other areas. This level of compatibility makes TerarkDB an attractive option for users seeking enhanced performance without sacrificing the familiar interface of RocksDB.