PostgreSQL asynchronous I/O

<div class="demo"><div class="head"><b>STORAGE READS</b><span id="aio">serial</span></div><div class="stage io"><div class="lane"><span>sync</span><div class="bars serial"><i></i><i></i><i></i></div></div><div class="lane"><span>AIO</span><div class="bars overlap"><i></i><i></i><i></i></div></div></div><div class="foot"><span id="iostatus">one request at a time</span><span>illustrative timing</span></div></div>

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let n=0;function tick(){document.querySelector('.serial').classList.toggle('active',!n);document.querySelector('.overlap').classList.toggle('active',!!n);document.getElementById('aio').textContent=n?'overlap':'serial';document.getElementById('iostatus').textContent=n?'requests in flight together':'one request at a time';n=1-n}tick();const t=setInterval(tick,1200);document.querySelector('.demo').onclick=()=>{clearInterval(t);tick()}