How do I ensure that my content is sent via gzip in Apache?

Question

Is there some setting that I can search for in Apache configurations to make sure that all pages, CSS, and JavaScript are sent via gzip?

Are they located in different places for different Operating Systems (if so, I am running Debian).

Answer 1

I put the following in my httpd.conf and it seems to work:

  # 20100709 added etag code
  FileETag MTime Size

  # 20100709 added compression START

  # 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 2.0.48
  # 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
  SetEnvIfNoCase Request_URI \
  \.(?:gif|jpe?g|png)$ no-gzip dont-vary

  # Make sure proxies don't deliver the wrong content
  Header append Vary User-Agent env=!dont-vary

  # 20100709 added compression END

This website has a great tester for seeing if your page is GZIP'd: http://www.whatsmyip.org/http_compression/

Answer 2

Install ySlow in Firefox and it will tell you which items are being gzipped.

Answer 3

RedBot, successor to the Cacheability Engine, does a really great job of testing a page and contents for several performance and cacheability metrics in a simple, easy-to-read grid format.

Example: http://redbot.org/?descend=True&uri=http://www.microsoft.com/en/us/default.aspx