wall clock time

基本解释

You have a pre-defined variable named total_time for the wall-clock time of the whole data collection.
有一個預定義的變量 total_time，它代表整個數據收集過程的時鍾時間。
A simple performance metric is wall clock time, or measuring the real-world delay between a request for a page and a finished rendering.
一個簡單的性能指標是掛鍾時間（wall clock time），或測量頁麪請求與完成呈現之間的實際延遲。
For some circumstances -- say, running the Web server, database, and browser locally on your own workstation -- wall clock time can be informative.
對於某些情況 —— 比如在您自己的工作站本地運行的 Web 服務器、數據庫和瀏覽器 —— 掛鍾時間能夠提供信息。