了解dmesg

$ man dmesg
dmesg - print or control the kernel ring buffer
The default action is to read all messages from kernel ring buffer.

dmesg 打印kernel ring缓冲区内容，那么kernel ring缓冲区里是啥内容呢？

The kernel ring buffer is a data structure that records messages related to the operation of the kernel. A ring buffer is a special kind of buffer that is always a constant size, removing the oldest messages when new messages come in
kernel ring 缓冲区是一种数据结构，用于记录与内核操作有关的信息。ring缓冲区是种特殊的缓冲区，它的大小是固定的，缓冲区满时会将最旧的信息去除