yum安装依赖环境有时候会出现：

Another app is currently holding the yum lock; waiting for it to exit...
  The other application is: yum
    Memory :  42 M RSS (438 MB VSZ)
    Started: Sat May 22 18:49:57 2021 - 00:08 ago
    State  : Traced/Stopped, pid: 59611

这时候其实是yum锁，就是你的yum被占用了。

解决方法：

rm -f /var/run/yum.pid

Another app is currently holding the yum lock; waiting for it to exit...