Thanks for reading it so carefully. Let me explain it one by one:<p>&gt; they optimized &quot;Round&quot; which took 18 seconds<p>This is CPU profile. The overall sampled time is 79 seconds. The Round() method took 18 seconds. This has no direct indication to scheduling latency.<p>&gt; by that reduced total cpu time from 53 to 23 seconds<p>This is about scheduling latency. In this experiment, we schedule 1000 pods on 1000 nodes and see how much time it took to schedule a pod, aka scheduling latency. Before the optimization, the latency is 53 seconds; after, 23 seconds. Of course, this is just one of the steps we kept optimizing.