She does mention:<p>&gt; each request was taking 6 &#x2F; 60 = 0.1s = 100ms of time <i>using-or-waiting-for-the-CPU</i>.<p>(emphasis mine)<p>In my original read, I thought her core count was greater than her load, so that would also be her direct time-on-cpu. Now I&#x27;m not so sure.<p>And while time-waiting-for-cpu might not be important to optimizing the codebase, you probably still want to know that your serving processes are waiting for CPU; after all, it is that number that your user&#x27;s browser is seeing (at least, between the two it is moreso that one). Such a result might indicate a larger machine or more machines are required, for example.