When a document is deleted, RavenDB will leave behind a "delete marker" which is called a Tombstone.
Where are They Used?
- Replication and ETL - this is needed so delete operations can be replicated to other nodes
- Indexes use tombstones in order to delete no longer relevant entries that refer to deleted documents
- Periodic Backup uses tombstones in order to backup "deletions" of documents
The tombstones are periodically cleaned.
Cleaning will occur only for tombstones that were already processed by the modules where they are used:
- Periodic Backup
- The tombstone retaining period is configurable with config entry name = Tombstones.CleanupIntervalInMin
- By default, the configuration value it is 5 minutes.