> [!SerializableXactHash] > <table><tr><td rowspan="4" width="25%"><img src="assets/wl_lw_serializablexacthash.png"></td><td><b>Wait Category</b></td><td>LWLock</td></tr><tr><td><b>Mechanism</b></td><td><code>SerializableXactHashLock</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"><b>SSI Identity Discovery Bottleneck</b>. To detect conflicts between sessions, Postgres must quickly find the "Predicate List" and "Status" for any transaction ID encountered during a scan.</td></tr></table>