In the video they say that they used many of Steve Souders' techniques to speed up the deliver of the files since most web servers aren't properly optimized out of the box
Looks like Google missed the part in Souders' High Performance Web Site where he talked about using ETag to speed up sites. :P
curl -I http://ajax.googleapis.com/ajax/libs/jquery/1.2.6/jquery.min.js
HTTP/1.1 200 OK
Last-Modified: Mon, 26 May 2008 18:45:05 GMT
Content-Type: application/x-javascript
Expires: Wed, 27 May 2009 17:39:22 GMT
Date: Tue, 27 May 2008 17:39:22 GMT
Cache-Control: public, max-age=31536000
Content-Length: 55740
Server: GFE/1.3
Oops, you are right. For some reason I thought using the If-None-Match header was the "right" way of doing this, it just adds flexibility to how you cache stuff.
"If you're not taking advantage of the flexible validation model that ETags provide, it's better to just remove the ETag altogether. The Last-Modified header validates based on the component's timestamp. And removing the ETag reduces the size of the HTTP headers in both the response and subsequent requests."
In the video they say that they used many of Steve Souders' techniques to speed up the deliver of the files since most web servers aren't properly optimized out of the box
Looks like Google missed the part in Souders' High Performance Web Site where he talked about using ETag to speed up sites. :P