> [!BufferIO] > <table><tr><td rowspan="4" width="25%"><img src="assets/wl_ipc_bufferio.png"></td><td><b>Wait Category</b></td><td>IPC</td></tr><tr><td><b>Mechanism</b></td><td><code>TerminateBufferIO</code></td></tr><tr><td><b>Operations</b></td><td><a href="Operations/Table/SeqScan">SeqScan</a>, <a href="Operations/Index/IndexScan">IndexScan</a>, <a href="Operations/Page/BitmapHeapScan">BitmapHeapScan</a></td></tr><tr><td><b>Resources</b></td><td><a href="Resources/disk IO">disk IO</a>, <a href="Resources/CPU">CPU</a></td></tr><tr><td colspan="3">This wait event is the synchronization point between the database and the operating system's I/O stack. When a backend process issues a read or write request for a 8KB page, it marks the buffer as "under I/O" and enters this state while it waits for the hardware and kernel to fulfill the request.</td></tr></table>