For a better performance, the server stores different data in a cache.

For quick access to user and group data, their information is stored and indexed in its cache. This index contains all searchable values. Should this index be corrupt, e.g. due to bad sectors of the hard disk or restoring a backup, this will be noticeable by missing search results. The index will then need to be recreated.

The Drive uses a cache for the search index. It allows identifying and searching for files in the Drive quickly. The cache can be cleared using the Maintenance application.