> [!NOTE] ![[assets/wl_lwlock_parallelvacuumdsa.png|256]]
>
> | | |
> | :--- | :--- |
> | **Wait Category** | LWLock |
> | **Mechanism** | `ParallelVacuumLock` |
> | **Operations** | [[Operations/Table/SeqScan]] |
> | **Resources** | [[Resources/RAM|Memory]], [[Resources/CPU|CPU]] |
>
> Contention on the **Maintenance Memory Allocator**. Parallel vacuum allows multiple worker processes to cooperatively clean up a single large table, most notably during the index vacuuming and heap-cleanup phases.