Introduction
TokuDB is a high-performance storage engine for MariaDB, optimized for write-intensive workloads. It is highly scalable and uses a storage technology that the developer, Tokutek, calls Fractal Tree Indexes. It can be used with no application or code changes instead of (and alongside) MyISAM, Aria, and InnoDB/XtraDB tables. It is ACID and MVCC compliant.
ACID compliance means that TokuDB transactions have atomicity, consistency, isolation, and durability. More information on ACID is available at http://en.wikipedia.org/wiki/ACID.
MVCC compliance means that TokuDB has multiversion concurrency control for database transactions. More information on MVCC is available at http://en.wikipedia.org/wiki/Multiversion_concurrency_control.
Fractal trees are a modification of B-trees, which is what InnoDB uses to store data (to be more accurate, InnoDB uses a balanced B+ tree). Whereas InnoDB has a single small cache for an entire data tree, TokuDB implements several large caches at multiple...