Announcements 11/3 – Doug Crockford from Yahoo! will be guest lecturer talking about "Ajax Performance"
Browser Cache Experiment how much are resources cached? research-part-2/ add transparent pixel image: with specific headers: Expires: Thu, 15 Apr :00:00 GMT Last-Modified: Wed, 22 Oct :49:57 GMT requests from the browser will have one of these response status codes: 200 – the browser does not have the image in its cache 304 – the browser has the image in its cache, but needs to verify the last modified date
Desired metrics What percentage of users view with an empty cache? # unique users with at least one 200 response total # unique users What percentage of page views are done with an empty cache? total # of 200 responses # of # of 304 responses
Cache Results 40-60% of users/day visit with an empty cache 75-85% of page views/day are primed cache