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 serve as a key/value store, with a schema layer for indexes and projections. 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 operates without a centralized lock manager, and transactional work in one thread does not block work in another. Block compression can be selected for each table; the documentation says it typically reduces information written to disk by 30–80%. Integrity features include end-to-end checksums, data 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. The reference guide describes portability to 64-bit systems supporting ANSI C11 and POSIX 1003.1, with build instructions for Linux, BSD, OS X and Windows. Tiered storage is experimental and not developed, tested or tuned for production use.

Who it suits

It suits developers and organisations building data-management systems that need a NoSQL engine with transactional storage options. Its key/value model and documented portability may also suit teams targeting supported 64-bit systems.

Limits

The free plan is open source under GNU GPL version 2 or version 3; other licensing terms require contacting MongoDB. Tiered storage is experimental and not developed, tested, or tuned for production scenarios.

Getting started

1. Review the WiredTiger documentation at https://source.wiredtiger.com/
2. Choose a supported environment such as Linux, *BSD, macOS, Windows, or another 64-bit POSIX system
3. Use the build instructions for the target platform
4. Use GNU GPL version 2 or version 3, or contact MongoDB about other licensing terms or technical support

Verdict

WiredTiger offers a broad set of storage, transaction and integrity capabilities as a free, open-source engine. Tiered storage remains experimental, and users seeking other licensing terms or technical support are directed to MongoDB.