Global deflate.conf for Apache

If you are running a LAMP infrastructure, this little code snippet is very helpful if you are serving lots of HTML, JavaScript and CSS-related information.

The mod_deflate module, which is part of the Apache 2.2 application, provides the DEFLATE output filter that allows output from your server to be compressed before being sent to the client over the network. Using the mod_deflate module, you can compress HTML, cross-side scripting (CSS), JavaScript, XML and other text-related files as high as 40% of their original size, thus reducing overall server network traffic. Although, the compression of the data may result in a higher CPU load of your LAMP/Web server, this overhead is to be expected as the server is having to do the compression work rather than forcing the user's end client (browser).

I designed a deflation configuration that can be dropped in the /etc/httpd/conf.d directory (commonly found on RHEL, Fedora and CentOS distros), so that is has global mod_deflate capabilities. Just drop the code snippet as the 'deflate.conf' into the directory as specified and bounce the Apache/httpd instance (i.e. /etc/init.d/httpd restart). However, if you are running Debian or Ubuntu distro, then I recommend looking at this article first (http://www.control-escape.com/web/configuring-apache2-debian.html) for locating where to put the actual deflate.conf file.

For debugging and performance tuning needs, I added a special filter format to the code that allows you to separate what is being compressed and the current ratio of such compression. Just add the following line to your httpd.conf:

CustomLog /path/to/the/deflate_log deflate

For those running virtual hosts, the above CustomLog entry can also be used for each website as well for easier log file reading needs.

NOTE: If you are hosting Drupal or Joomla sites, do not use this deflation configuration in conjunction with the Apache mod_gzip module. It has authenticated and unauthenticated session issues (i.e. it tries to do double compression, thus crushing the site -- just displaying white pages). Drupal actually has a gzip module (http://drupal.org/project/css_gzip) to fix this issue.

<IfModule mod_deflate.c>
                      
                      SetOutputFilter DEFLATE
                      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$ no-gzip dont-vary
                      SetEnvIfNoCase Request_URI \.avi$ no-gzip dont-vary
                      SetEnvIfNoCase Request_URI \.mov$ no-gzip dont-vary
                      SetEnvIfNoCase Request_URI \.mp3$ no-gzip dont-vary
                      SetEnvIfNoCase Request_URI \.mp4$ no-gzip dont-vary
                      SetEnvIfNoCase Request_URI \.rm$ no-gzip dont-vary
                      
                       <FilesMatch "\.(js|css|html|xml|x?html?|php)$">
                        AddOutputFilterByType DEFLATE text/plain
                        AddOutputFilterByType DEFLATE text/html
                        AddOutputFilterByType DEFLATE text/xml
                        AddOutputFilterByType DEFLATE text/css
                        AddOutputFilterByType DEFLATE application/xhtml+xml
                        AddOutputFilterByType DEFLATE application/xml
                        AddOutputFilterByType DEFLATE image/svg+xml
                        AddOutputFilterByType DEFLATE application/rss+xml
                        AddOutputFilterByType DEFLATE application/atom_xml
                        AddOutputFilterByType DEFLATE application/x-javascript
                        AddOutputFilterByType DEFLATE application/javascript
                        AddOutputFilterByType DEFLATE application/json
                        AddOutputFilterByType DEFLATE application/x-httpd-php
                        AddOutputFilterByType DEFLATE application/x-httpd-fastphp
                        AddOutputFilterByType DEFLATE application/x-httpd-eruby
                        AddOutputFilterByType DEFLATE text/html
                       </FilesMatch>
                      
                      DeflateCompressionLevel 5
                      
                      BrowserMatch ^Mozilla/4 gzip-only-text/html
                      BrowserMatch ^Mozilla/4\.0[678] no-gzip
                      BrowserMatch \bMSIE !no-gzip !gzip-only-text/html
                      
                      DeflateFilterNote Input instream
                      DeflateFilterNote Output outstream
                      DeflateFilterNote Ratio ratio
                      
                      LogFormat '"%r" %{outstream}n/%{instream}n (%{ratio}n%%)' deflate
                      
                      </IfModule>
                      

Select all Open in new window