（总结）RHEL/CentOS 5.x使用yum安装zend-optimizer
1、下载并运行这个脚本：wget -q -O - http://www.atomicorp.com/installers/atomic | sh
2、运行完上面的脚本后，会看到/etc/yum.repos.d/目录下多了一个名字为atomic.repo的源，内容如下：
# Name: Atomic Rocket Turtle RPM Repository for CentOS / Red Hat Enterprise Linux 5 -
# URL: http://www.atomicrocketturtle.com/
# Note: This isn't covered by ASL support. -Scott
[atomic]
name = CentOS / Red Hat Enterprise Linux $releasever - atomicrocketturtle.com
mirrorlist = http://www.atomicorp.com/mirrorlist/atomic/centos-5-$basearch
#mirrorlist = http://www.atomicorp.com/channels/atomic/centos/5/mirrors-atomic
enabled = 1
priority = 1
protect = 0
gpgkey = file:///etc/pki/rpm-gpg/RPM-GPG-KEY.art.txt
gpgcheck = 1
# Almost Stable, release candidates for [atomic]
# Note these are not supported by anyone. -Scott
[atomic-testing]
name = CentOS / Red Hat Enterprise Linux $releasever - atomicrocketturtle.com - (Testing)
mirrorlist = http://www.atomicorp.com/mirrorlist/atomic-testing/centos-5-$basearch
enabled = 0
priority = 1
protect = 0
gpgkey = file:///etc/pki/rpm-gpg/RPM-GPG-KEY.art.txt
gpgcheck = 1
# Untested, Unstable, known buggy, and incomplete packages.
# Note, you shouldn't be here unless you are me. -Scott
#[atomic-bleeding]
#name = CentOS / Red Hat Enterprise Linux $releasever - atomicrocketturtle.com - (Bleeding)
#baseurl = http://www.atomicorp.com/channels/atomic-bleeding/centos/5/$basearch/
#enabled = 0
#priority = 1
默认开启第一个就行。
3、使用yum安装zend-optimizer
yum install php-zend-optimizer
