> [!ProcSignalBarrier] > <table><tr><td rowspan="4" width="25%"><img src="assets/wl_ipc_procsignalbarrier.png"></td><td><b>Wait Category</b></td><td>IPC</td></tr><tr><td><b>Mechanism</b></td><td><code>ProcSignalBarrier</code></td></tr><tr><td><b>Operations</b></td><td><a href="Operations/Table/SeqScan">SeqScan</a>, <a href="Operations/Tuple/ModifyTable">ModifyTable</a></td></tr><tr><td><b>Resources</b></td><td><a href="Resources/CPU">CPU</a>, <a href="Resources/RAM">Memory</a></td></tr><tr><td colspan="3">This wait event represents a <b>Global Consensus Stall</b>. Certain operations in Postgres require that all backends be "on the same page"—for example, when a relation is dropped, every backend must invalidate its internal cache to avoid accessing a file that no longer exists.</td></tr></table>