alfred westerveld's Bookmarks tagged optimization →  View Popular

RewriteEngine on
RewriteOptions Inherit

#Check to see if browser can accept gzip files.
ReWriteCond %{HTTP:accept-encoding} (gzip.*)

#make sure there's no trailing .gz on the url
ReWriteCond %{REQUEST_FILENAME} !^.+\.gz$

#check to see if a .gz version of the file exists.
RewriteCond %{REQUEST_FILENAME}.gz -f

#All conditions met so add .gz to URL filename (invisibly)
RewriteRule ^(.+) $1.gz [L]

Compress your images the right way

Saving your images with Photoshop and "save for web" doesn't mean they are optimized. There is more to image optimization than saving photos as Jpeg and navigation elements as PNG. Even lossless formats like PNG can often be compressed to 50% of it's original size without quality loss if you use the right software.

I have successfully used the freely available OptiPNG. OptiPNG compresses PNG, GIF and other formats. It comes with source code for Unix or as a precompiled binary for Windows. Build instructions for Unix are found in the README. It is a command line tool and can be run with wildcards to automatically optimize all images in a given directory.

You can measure the effective bandwidth of your users on your site
relatively easily, and if the effective bandwidth of users viewing
your pages is substantially below their available downstream bandwidth, it
might be worth attempting to improve this.

Before giving the browser any
external object references (<img src="...">, <link rel="stylesheet"
href="...">, <script src="...">, etc), record the current time.
After the page load is done, subtract the time you began, and include that
time in the URL of an image you reference off of your server.

Sample javascript implementing this: