为什么大多数软件的 i386 版本与 x86_64 版本一起安装在 CentOS 64 位系统上？
# yum install php-xml
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
Setting up Install Process
Package php-xml-5.3.12-5.el5.art.x86_64 already installed and latest version
Package php-xml-5.3.12-5.el5.art.i386 already installed and latest version
Nothing to do