e and the time-critical logic can be
understood as two different ways of managing <em>peer request queues</em>.</p>
<p><tt class="docutils literal">sequential_download</tt> will simply wait until a queue slot opens up, and
request the next piece in the sequence. This mechanism is even simpler than the
classic &quot;rarest-first&quot; algorithm; it does a good job of keeping request queues
full, thus saturating available download bandwidth; and pieces do arrive
<em>roughly</em> in-order. However, it's sub-op