This one escaped me for a long time and I never saw a decent example of it in any of the documentation.
GZip compression saves on network bandwidth as files are compressed during transport between the HTTP Server and browser/client. If you already use Apache HTTP or a similar webserver to front Tomcat, this is not always necessary, but in cases where you expose your appserver directly, even if it is just for testing, you may want to add this configuration item as it increases the perceived speed of the application.
The solution is simple:
- To be safe, first stop the server and backup your configuration files
- Look in the /TOMCAT/conf installation folder.
- In the ‘server.xml’ file, you will find a line resembling…
<Connector port="8080" protocol="HTTP/1.1" connectionTimeout="20000" redirectPort="8443" />
- This one controls the HTTP/1.1 connections, add a new value to the list…
- NOTE You might also see a value for for AJP/1.3, unfortunately compression only works for HTTP:
<Connector port="8009" protocol="AJP/1.3" redirectPort="8443" />
- Restart your server.
I spend a lot of my time tweaking the performance of web applications, in addition to optimizing code it’s also necessary to verify that your server settings are also optimized for network performance to reduce bandwidth usage and thus client response times.
NOTE: This is a tradeoff between CPU and network performance, it works by compressing the content on the server just before it is sent over the wire…. when the client receives it, it then also spends some of it’s resources to decompress the content.
The Apache HTTP server provided mod_deflate (for 2.x) or mod_gzip (for 1.3).
Here’s a quick start as well as a few references:
1. Uncomment the module:
LoadModule deflate_module modules/mod_deflate.so
2. Add the following (modify if required):
AddOutputFilterByType DEFLATE text/*
AddOutputFilterByType DEFLATE application/xml
AddOutputFilterByType DEFLATE application/xhtml+xml
# Insert filter
# 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 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 2.0.48
# the above regex won’t work. You can use the following
# workaround to get the desired effect:
BrowserMatch \bMSI[E] !no-gzip !gzip-only-text/html
# Don’t compress images or ZIP/GZ/7Z
SetEnvIfNoCase Request_URI \
\.(?:gif|jpe?g|png|zip|7z|gz)$ no-gzip dont-vary
# Make sure proxies don’t deliver the wrong content
Header append Vary User-Agent env=!dont-vary
For years I was an advocate of PKZip and WinZip (That I own a “floppy” disk of), but after discovering the advantages and freedom of open-source, I discovered 7Zip.
7-Zip is a file archiver with the high compression ratio. The program supports 7z, ZIP, CAB, RAR, ARJ, LZH, CHM, GZIP, BZIP2, Z, TAR, CPIO, RPM and DEB formats.
While it’s only available on Windows, similar software is native on most other Operating Systems, Microsoft added only meager support in Windows XP (which in fact often crashes machines).