An Omnidex Grid consists of one or more computers that are used in combination to satisfy Omnidex queries. Some Omnidex Grid’s are placed on one or more large, multi-processor computers. Other Omnidex Grid’s are placed on an array of inexpensive, commodity, desktop PC’s. Both types of grids perform well, and each has distinct advantages.

An Omnidex Grid always will have a grid controller and a collection of grid nodes. The grid controller coordinates all activity on the grid and communicates between the user and the underlying grid nodes. The grid nodes perform all of the work of housing and indexing the data, as well as fulfilling the queries. The grid controller and the grid nodes may all reside on the same computer, or they may be distributed between multiple grid servers as needed for performance and scalability.

Omnidex Grids provide the advantage of automatic SQL optimization across all nodes. When a database is partitioned manually, the application must perform the tasks of routing queries to the appropriate partitions and merging their results. With an Omnidex Grid, Omnidex will accept SELECT statements to the grid controller, automatically route them to the appropriate nodes and merge the results. This alleviates the work done at the application and allows Omnidex to fully optimize the query.

Many Omnidex Grids are created as an Omnidex Snapshot, meaning that the underlying data is distributed into flat files across multiple directories or servers. This becomes a very high-performing solution that can satisfy a wide variety of queries very quickly. Omnidex Grids can also be created against the underlying database, though the nodes then remain tethered to the servers hosting the database.

The Omnidex Grid at DISC consists of five Dell Dimension 9150 PC’s, each with between 2 GB and 4 GB of memory. Each has two or three commodity 500 GB internal SATA drives. All servers are running Microsoft Windows XP Professional, SP2. The machines are connected using a 1 gigabit switch for fast inter-machine transfers. The total hardware acquisition cost was under $10,000. The Omnidex Grid at DISC allocates one of these five machines as the grid controller and allocates the other four machines as grid servers housing the grid nodes.