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mod deflate

Gzip is the most popular and effective compression method. Most modern web browser supports and accepts compressed data transfer. By gziping response time can reduced by 60-70% as compare to normal web page. The end result is faster web site experience for both dial up (they're not dead yet - I've dial up account for backup purpose) and broadband user. I've already written about speeding up Apache 2.x web access or downloads with mod_deflate.

mod_compress for Lighttpd 1.4.xx

Lighttpd 1.4.xx supports gzip compression using mod_compress. This module can reduces the network load and can improve the overall throughput of the webserver. All major http-clients support compression by announcing it in the Accept-Encoding header as follows:

Accept-Encoding: gzip, deflate

If lighttpd sees this header in the request, it can compress the response using one of the methods listed by the client. The web server notifies the web client of this via the Content-Encoding header in the response:

Content-Encoding: gzip

This is used to negotiate the most suitable compression method. Lighttpd support deflate, gzip and bzip2.

Configure mod_compress

Open your lighttpd.conf file:
# vi /etc/lighttpd/lighttpd.conf
Append mod_compress to server.modules directive:
server.modules += ( "mod_compress" )
Setup compress.cache-dir to stored all cached file:
compress.cache-dir = "/tmp/lighttpdcompress/"
Finally, define mimetypes to get compressed. Following will allow to compress javascript, plain text files, css file,xml file etc:

compress.filetype           = ("text/plain","text/css", "text/xml", "text/javascript" )

Save and close the file. Create /tmp/lighttpdcompress/ file:
# mkdir -p /tmp/lighttpdcompress/
# chown lighttpd:lighttpd /tmp/lighttpdcompress/

Restart lighttpd:
# /etc/init.d/lighttpd restart

How do I enable mod_compress per virtual host?

Use conditional $HTTP host directive, for example turn on compression for theos.in:

$HTTP["host"] =~ "theos\.in" {
  compress.cache-dir = "/var/www/cache/theos.in/"

PHP dynamic compression

Open php.in file:
# vi /etc/php.ini
To compress dynamic content with PHP please enable following two directives:
zlib.output_compression = On
zlib.output_handler = On

Save and close the file. Restart lighttpd:
# service lighttpd restart

Cleaning cache directory

You need to run a shell script for cleaning out cache directory.

See also:

You can speed up downloads or web page access time with Apache mod_deflate module. The mod_deflate module provides the DEFLATE output filter that allows output from your server to be compressed before being sent to the client over the network.

This decreases the amount of time and data transmitted over the network, resulting in faster web experience or downloads for visitors.

Make sure mod_deflate included with your Apache server (by default it is now installed with all modern distro).

How can I speed up downloads from my Apache 2.0 server?

Open httpd.conf file using a text editor such as vi:
# vi httpd.conf

Append following line:
LoadModule deflate_module modules/mod_deflate.so

Append following configuration <Location /> directive:
<Location />
AddOutputFilterByType DEFLATE text/html text/plain text/xml

Above line only compress html and xml files. Here is the configuration from one of my production box:
<Location />
AddOutputFilterByType DEFLATE text/plain
AddOutputFilterByType DEFLATE text/xml
AddOutputFilterByType DEFLATE application/xhtml+xml
AddOutputFilterByType DEFLATE text/css
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/x-httpd-php
AddOutputFilterByType DEFLATE application/x-httpd-fastphp
AddOutputFilterByType DEFLATE application/x-httpd-eruby
AddOutputFilterByType DEFLATE text/html

Close and save the file. Next restart apache web server. All of the above extension file should compressed by mod_deflate:
# /etc/init.d/httpd restart

You can also specify specific directory and enabling compression only for the html files. For example /static/help/ directory:
<Directory "/static/help">
AddOutputFilterByType DEFLATE text/html

In real life, there are issues with compressing other types of files such as mp3 or images. If you don't want to compress images or mp3 files, add following to your configuration:
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

Please note that this processing takes additional CPU and memory on your server as well as on the client browser. So you must make decision which document you need to compress (thanks to mdxp).

See also: