个字节的时间，表示网络片段发现数据包的时间戳。

4 bytes of time to indicate the time stamp that the packet was seen by the network snippet.

youdao

是浏览器的初始化到从服务器接收到的第一个字节的时间。

TTFB (or Time to first byte) is the duration from the initial network request being initiated by the browser to the first byte being received from the server.

youdao

这样做的优点是节省了Perl每次将脚本从源代码编译成字节代码的时间。

What this does is save Perl from having to compile the script from its source code into the bytecode each time.

youdao