WiredTiger

What WiredTiger is

WiredTiger is a free, open-source NoSQL data engine for data management, developed and maintained by MongoDB, Inc., where it is the principal database storage engine. It can also be used as a key/value store, with a schema layer for indexes and projections. Its storage options include row-oriented and column-oriented formats as well as log-structured merge trees. WiredTiger supports ACID transactions with standard isolation levels and checkpoint-level or commit-level durability. Its optimistic concurrency control has no centralized lock manager, and transactional work in one thread does not block operations in other threads. Block compression can be configured per table; the documentation says it typically reduces information written to disk by 30–80%. Integrity features include checksums, verification, salvage support, and a no-overwrite design intended to guard against torn writes. The overview describes support for petabyte tables, records up to 4 GB, and 64-bit record numbers. Encryption is supported. WiredTiger is documented for Linux, *BSD, macOS, Windows, and other 64-bit POSIX systems. Tiered storage is experimental and is not developed, tested, or tuned for production scenarios. The plan is free under GNU GPL version 2 or version 3; MongoDB handles other licensing terms and technical support.