> [!NOTE] ![[assets/wl_lwlock_syncscan.png|256]] > > | | | > | :--- | :--- | > | **Wait Category** | LWLock | > | **Mechanism** | `SyncScanLock` | > | **Operations** | [[Operations/Table/SeqScan]] | > | **Resources** | [[Resources/RAM|Memory]], [[Resources/CPU|CPU]] | > > Contention on the **Scan Coordination Layer**. Synchronized scans (governed by `synchronize_seqscans`) are a performance optimization designed to reduce I/O pressure on massive tables by allowing multiple concurrent sequential scans to share the same physical page reads from the OS cache or disk.