> [!NOTE] ![[assets/wl_lwlock_multixactoffsetbuffer.png|256]] > > | | | > | :--- | :--- | > | **Wait Category** | LWLock | > | **Mechanism** | `MultiXactOffsetControlLock` | > | **Operations** | [[Operations/Tuple/ModifyTable]], [[Operations/Table/SeqScan]] | > | **Resources** | [[Resources/RAM|Memory]], [[Resources/CPU|CPU]] | > > **Shared Lock Indexing Cache Barrier**. Every time the engine encounters a shared row lock, it must first check the "Offset" SLRU to find the starting position of the lock holders in the "Member" SLRU.