Depending on your Vault release, you can specify whether just the latest or released versions, or all versions of a file are included in the re-index.
The latest versions are reindexed.
The latest versions, released versions, and pending released versions are re-indexed.
This is the default option.
Re-indexes all of the files in the vault.
Clients can access the vault while it is being re-indexed. Not all properties may be up-to-date until the re-indexing has finished.