Chico_Loco - 10:43 pm on Jan 15, 2008 (gmt 0)

g1smd,

From what I understand, the optimal way to move to load images is indeed to have them servered by a different server, but with certain prerequisites. For the most part, the real advantage comes from being able to use a stripped-down super-light HTTP server for the serving of static content (your images, CSS, JS files, etc..). In this way, the HTTP server can be pre-compiled without support for PHP, MySQL, Perl, mod_rewrite, etc., etc.. This gives the server a much smaller memory footprint and quick load-time. Naturally, your main Web server will retain such functionality. This all being in addition to the browser's parallel-loading advantage!

There's a few issues with having an images.domain.tld static file server though. If you have a single box with both your main HTTP server and your optimized static file server, you can't run both of them on port 80 on the same IP. One option is to re-port your static file server to another port, eg. 81. This is obviously a pain because your images will need to be referenced as images.domain.tld:81..., which can cause logistics problems down the road.

The better way to do it is to have a separate box (or the same box with 2 unique IP addresses). This way you can map your main domain to one IP, the static server which is the sub-domain to the other IP, and both can run on port 80!

It's quite an interesting subject that I've spent a bit of time on... To be honest though, I wouldn't recommend doing any of this unless you have a combination of servers under heavy load, along with an obvious problem in page-load times, but the load-speed increase is very slight in the majority of cases, to be honest. It really only matters with very large pages and very high traffic levels. Hope this helps.