> [!PerXactPredicateList] > <table><tr><td rowspan="4" width="25%"><img src="assets/wl_lw_perxactpredicatelist.png"></td><td><b>Wait Category</b></td><td>LWLock</td></tr><tr><td><b>Mechanism</b></td><td><code>SerializablePredicateListLock</code></td></tr><tr><td><b>Operations</b></td><td><a href="Operations/Table/SeqScan">SeqScan</a>, <a href="Operations/Index/IndexScan">IndexScan</a></td></tr><tr><td><b>Resources</b></td><td><a href="Resources/RAM">Memory</a>, <a href="Resources/CPU">CPU</a></td></tr><tr><td colspan="3">Contention on the <b>Parallel SSI Coordination Layer</b>. When a serializable transaction launches parallel workers, those workers must participate in the same dependency graph as the leader to ensure the serializable guarantee is maintained across the whole process group.</td></tr></table>