[hongchaodeng]

Thanks for reading it so carefully. Let me explain it one by one:

> they optimized "Round" which took 18 seconds

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.

> by that reduced total cpu time from 53 to 23 seconds

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.