GeoServer does not come built-in with support for Pregeneralized Features; it must be installed through an extension.
Installing the Pregeneralized Features extension¶
Visit the website download page, locate your release, and download: geoserver-2.21-SNAPSHOT-feature-pregeneralized-plugin.zip
Ensure to match plugin (example 2.21-SNAPSHOT above) version to the version of the GeoServer instance.
Extract the contents of the archive into the
WEB-INF/libdirectory of the GeoServer installation.
Adding a Pregeneralized Features data store¶
If the extension is properly installed, Generalized Data Store will be listed as an option when creating a new data store.