apache性能优化之启用gzip压缩
首先查看apache是否加载了mod_deflate.so模块，如果没有需要安装加载。
找到并下载和当前apache版本相同的源码文件，解压缩到/home目录下，
在apache安装目录下执行：

/usr/local/apache2/bin/apxs -i -c /home/httpd-2.0.63/modules/filters/mod_deflate.c会自动在 httpd.conf添加

LoadModule deflate_module modules/mod_deflate.so添加如下设置：

<IfModule mod_deflate.c>
<Location />
#Insert filter
SetOutputFilter DEFLATE
# Netscape 4.x has some problems…   
BrowserMatch ^Mozilla/4 gzip-only-text/html
# Netscape 4.06-4.08 have some more problems
BrowserMatch ^Mozilla/4\.0[678] no-gzip
# MSIE masquerades as Netscape, but it is fine
# BrowserMatch \bMSIE !no-gzip !gzip-only-text/html
# NOTE: Due to a bug in mod_setenvif up to Apache 2.0.59
# the above regex won’t work. You can use the following
# workaround to get the desired effect:
# BrowserMatch \bMSIE !no-gzip !gzip-only-text/html force-gzip
BrowserMatch \bMSIE !no-gzip !gzip-only-text/html

# Don’t compress images and other
SetEnvIfNoCase Request_URI .(?:gif|jpe?g|png)$ no-gzip dont-vary
SetEnvIfNoCase Request_URI .(?:exe|t?gz|zip|bz2|sit|rar)$ no-gzip dont-vary
SetEnvIfNoCase Request_URI .(?:pdf|doc)$ no-gzip dont-vary
AddOutputFilterByType DEFLATE text/html text/plain text/xml text/css
AddOutputFilterByType DEFLATE application/x-javascript
# Make sure proxies don’t deliver the wrong content
Header append Vary User-Agent env=!dont-vary

#DeflateFilterNote ratio ratio_info
#LogFormat '"%v %h %l %u %t “%r" %>s %b "%{Referer}i" "%{User-Agent}i"" (%{ratio}n)' deflate
#CustomLog logs/deflate_log deflate
</Location>
</IfModule>停止apache服务./apachectl stop，报错如下：
Cannot load /usr/local/apache2/modules/mod_deflate.so into server: /usr/local/apache2/modules/mod_deflate.so: undefined symbol: deflate解决如下：

vi /usr/local/apache2/bin/apr-config
修改LDFLAGS=" " 为 LDFLAGS="-lz"停止启动服务：仍提示：
DeflateFilterNote not allowed here
CustomLog not allowed here

注释掉后，正常。