Backpressure

<div class="v"><header><b>BACKPRESSURE</b><span id="state"></span></header><main><div class="meter"><div class="fill" id="fill"></div></div><div class="rates" id="rates"></div></main><footer>demand controls the source</footer></div>

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let n=0;const fill=[20,48,80,95,66,35];function draw(){document.getElementById("fill").style.width=fill[n]+"%";document.getElementById("rates").textContent=n>=3?"producer  ↓  |  consumer →":"producer →  |  consumer →";document.getElementById("state").textContent=n>=3?"slow producer":"buffer filling";n=(n+1)%fill.length}draw();setInterval(draw,850)