> [!WALWrite] > <table><tr><td rowspan="4" width="25%"><img src="assets/wl_io_walwrite.png"></td><td><b>Wait Category</b></td><td>IO</td></tr><tr><td><b>Mechanism</b></td><td><code>XLogWrite</code></td></tr><tr><td><b>Operations</b></td><td><a href="Operations/Tuple/ModifyTable">ModifyTable</a>, <a href="Operations/Distributed/Redistribute">Redistribute</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">That a process is stalled while waiting for the operating system to complete a write request to a Write-Ahead Log (WAL) segment. Unlike <code>WalSync</code>, which waits for a disk flush, <code>WalWrite</code> is simply the movement of data from the database process to the kernel's write queue or the physical disk controller.</td></tr></table>