https://blog.wongcw.com/2018/08/29/%e8%b0%81%e8%af%b4linux%e4%b8%8d%e9%9c%80%e8%a6%81%e6%b8%85%e7%90%86%e5%9e%83%e5%9c%be%ef%bc%9f%e7%94%a8journalctl%e6%b8%85%e7%90%86%e8%bf%913g%e6%97%a5%e5%bf%97%e6%96%87%e4%bb%b6/
谁说Linux不需要清理垃圾?用journalctl清理近3G日志文件