The Dgidx component organizes acquired records into a structure, partially precomputes results that are used by the Dgraph, and creates the Endeca index.
The Dgidx is part of the MDEX Engine installation package, and as such it is installed on both the ITL server and the MDEX Engine server. Since Dgidx is part of the offline processing that runs during baseline updates, the best practice is to run it on the ITL server (the Deployment Template implements this practice with its scripts).
At a very high level, the Dgidx process consists of the following steps:
As part of its processing, Dgidx sorts the acquired records and produces navigational, text, and wildcard indexes.
Dgidx relies on the operating system caching of indexes on disk and uses memory-mapped I/O to retrieve its indexes. This affects the size of the virtual memory allocated to the Dgidx working process, which can increase periodically.
For more information about memory considerations and the way the MDEX Engine uses memory, see the Oracle Commerce MDEX Engine Performance Tuning Guide.
