Apache 2.2 で gzip圧縮

Apache2.2がHTTPの通信をする際、gzip圧縮をして転送容量を下げることができます。昔（1.3）の頃から既に出来ましたけど、設定が微妙どころかかなり多くの箇所が変更になったので以下メモ書き。

ちなみに今イチ理解してないんだぜ。

参考：http://www.pinkdragon.net/doc_lib/contents/ja/apache_2_2_man/mod/mod_deflate.html

<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 2.0.48
# 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

</Location>