An in-memory data grid (IMDG) is a data structure that resides entirely in RAM (random access memory), and is distributed among multiple servers. Recent advances in 64-bit and multi-core systems have made it practical to store terabytes of data completely in RAM, obviating the need for electromechanical mass storage media such as hard disks.
According to industry analyst firm Gartner Inc., IMDGs are suited to handle big data's "big-three V's": velocity, variability, and volume. IMDGs can support hundreds of thousands of in-memory data updates per second, and they can be clustered and scaled in ways that support large quantities of data. Specific advantages of IMDG technology include:
- Enhanced performance because data can be written to, and read from, memory much faster than is possible with a hard disk.
- The data grid can be easily scaled, and upgrades can be easily implemented.
- A key/value data structure, rather than a relational structure, provides flexibility for application developers.
- The technical advantages provide business benefits in the form of faster decision making, greater productivity, and improved customer service.
Applications that can benefit from IMDG include financial-instrument pricing in banks, shopping carts in e-commerce, user-preference calculations in Web applications, reservation systems in the travel industry, and cloud applications.