解决CentOS/RHEL 7中，Yum命令失败并显示“另一个应用程序当前持有 yum锁定”的教程

yum list

Loaded plugins: fastestmirror, langpacks
Existing lock /var/run/yum.pid: another copy is running as pid 13023.
Another app is currently holding the yum lock; waiting for it to exit...
  The other application is: PackageKit
    Memory :  26 M RSS (430 MB VSZ)
    Started: Sat Sep 30 18:31:21 2022 - 00:33 ago
    State  : Sleeping, pid: 13023

ps -ef | grep 13023 
root 13023 11813 3 18:31 ? 00:00:04 /usr/bin/python /usr/share/PackageKit/helpers/yum/yumBackend.py

kill -9 13023

或者

pkill PackageKit