安装过程种有很多报错，这里我就不一一解释。
wget https://www.percona.com/downloads/XtraBackup/Percona-XtraBackup-2.3.5/binary/redhat/6/x86_64/percona-xtrabackup-2.3.5-1.el6.x86_64.rpm
yum install perl-DBD-MySQL perl-Time-HiRes perl-IO-Socket-SSL
安装epel源，是为了出现 libev.so4的报错。其实就是使用epel源来安装Libev
rpm -ivh http://mirrors.ustc.edu.cn/fedora/epel/6/x86_64/epel-release-6-8.noarch.rpm yum install libev
出现这个 libnuma.so.1()(64bit) is needed by依赖
yum -y install numactl*
然后rpm xtrabackup