The incremental generation work by only parsing and generating the content of the wiki which has changed since the last generation. It relies on a incremental generation file which store various data associated with each element in the wiki, and the last time of the generation.
Location of the file
The file is stored by default at the root of the wiki source[1]
In the case where there are more than one root directory, the first root will be used
, under the name__WikiState__.xml name. However, it is possible to set the file location by using the "incrementalGenerationFile" generation option.