Monday, May 07, 2007

Does Anybody Web-Cache Anymore?

Warning: this is another technical blog. No pictures, no human interest. Sorry.

From the early days of the DubDubDub, web-browers have used a cache to speed page viewing. In non-tech terms, the browser program saves all those bits of pages in a temporary location so that if you go back and view an old page again, you wouldn't have to pull all those buttons and logos over the network a second time.

As an early webmaster, I was well aware of this feature and made efforts to re-use graphic images in my pages. If I had the same logo on every page, the HTML code actually pointed to one single image file. If someone visited five pages, that logo still flew over the network only once.

I'm not seeing this happen anymore. While I know my web-browser is happily saving pages and images in its cache, I don't think it's actually getting a chance to use them.

I'm sitting in the WiFi Chair at my parents house, struggling with an intermittent connection. Frequently, I'll lose my connection and have to re-load a page. I also use MenuMeters, a tool to show me real-time network throughput. I can watch all those images load and reload over the network, even when I've just been to that page.

I suspect, due to Web 2.0 type smart pages, nothing is being cached. It's easy enough to do. Up in the header of the page, you can say 'pragma: no-cache" and force the browser to pull it fresh each time. This has the advantage that no one has stale pages, and if everyone were on high-speed internet, maybe it makes sense.

I've also seen problems with web authoring tools. I use iWeb on my main site and I've noticed that even though I re-use certain graphic elements on multiple pages, the authoring program never attempts to reuse image files in its code. For every page, the logo or button is rendered fresh and saved in a page-specific image directory. So, even though I re-use images, as far as the web-browser is concerned, none of these are the same. It has to load the same button fresh for every page visited on my site.

I could fix this manually, but I'm too lazy. I use a web-authoring tool rather than hand-coding the page because I value my time and I suspect almost everyone who visits the site has high-speed internet and would never notice the slowdown.

So, my question. Is the web-cache just one of those obsolete features that isn't actually used anymore? Should I just turn off my cache to save hard disk and forget the capability exists? If so, it's a little sad.


Wathsala Vithanage said...

This is a big problem in the developing world! Most of the traffic is geared towards sites like Facebook but caching is not respected.

Henry Melton said...

Interesting work on moving your bandwidth to a different time. I read your slides at your blog