> [!Promote] > <table><tr><td rowspan="4" width="25%"><img src="assets/wl_ipc_promote.png"></td><td><b>Wait Category</b></td><td>IPC</td></tr><tr><td><b>Mechanism</b></td><td><code>Promote</code></td></tr><tr><td><b>Operations</b></td><td><a href="Operations/Distributed/Redistribute">Redistribute</a></td></tr><tr><td><b>Resources</b></td><td><a href="Resources/CPU">CPU</a>, <a href="Resources/disk IO">disk IO</a></td></tr><tr><td colspan="3"><b>Cluster Role Transition Barrier</b>. During promotion, the database must finalize all received WAL records, shut down the WAL Receiver, increment the timeline ID, and create the timeline history file before it can begin accepting read-write traffic.</td></tr></table>