# Maintenance Workers (The Cleaning Crew)
These are the background workers responsible for keeping the Cafe clean and the ledgers organized.
- **AutoVacuum**: The cleaning crew that removes dead tuples from the ledger.
![[AutoVacuumMain]]
- **Checkpointer & BgWriter**: The staff who move scribbled notes from the Diary (WAL) to the permanent filing cabinets (Data Files).
![[CheckpointerMain]]
![[BgWriterMain]]
![[BgWriterHibernate]]
- **Archiver & SysLogger**: The record-keepers who store old Diary pages and log complaints.
![[ArchiverMain]]
![[SysLoggerMain]]