apache文件所在目录 modules/metadata/mod_expires.c
编译，使用apxs工具
apachepath/bin/apxs -c -i -a mod_expires.c
编译完后，自动加了LoadModule
httpd.conf配置
<IfModule expires_module>
ExpiresActive On
ExpiresByType image/gif "access plus 300 minutes"
ExpiresByType image/jpeg "access plus 300 minutes"
ExpiresByType image/png "access plus 300 minutes"
ExpiresByType text/css "access plus 3 minutes"
ExpiresByType application/x-shockwave-flash "access plus 300 minutes"
#ExpiresByType image/gif "access plus 3 minutes"
#ExpiresByType image/jpeg "access plus 3 minutes"
#ExpiresByType image/png "access plus 3 minutes"
#ExpiresByType text/css "access plus 3 minutes"
#ExpiresByType application/x-shockwave-flash "access plus 3 minutes"
#ExpiresDefault "now plus 1 day"
</IfModule>
