Tokyo Cabinet is a library of routines for managing a database. It is the successor of QDBM. Tokyo Cabinet runs very fast. For example, the time required to store 1 million records is 1.5 seconds for a hash database and 2.2 seconds for a B+ tree database. Moreover, the database size is very small. For example, the overhead for a record is 16 bytes for a hash database, and 5 bytes for a B+ tree database. Furthermore, the scalability of Tokyo Cabinet is great. The database size can be up to 8EB.