> [!NOTE] ![[assets/wl_lwlock_notifyslru.png|256]]
>
> | | |
> | :--- | :--- |
> | **Wait Category** | LWLock |
> | **Mechanism** | `NotifySLRULock` |
> | **Operations** | [[Operations/Other/FunctionScan]] |
> | **Resources** | [[Resources/RAM|Memory]], [[Resources/CPU|CPU]] |
>
> Contention on the **Notification Cache Management Layer**. While `NotifyBuffer` handles specific page updates, `NotifySLRU` is required for any operation that interacts with the SLRU mechanism itself—such as determining which message pages are currently resident in RAM or advancing the queue tail.