tag:blogger.com,1999:blog-2564511777660450660.post6977388229740493101..comments2008-07-23T13:01:45.889-06:00mndrixhttp://www.blogger.com/profile/00943372190551332722noreply@blogger.comBlogger4125tag:blogger.com,1999:blog-2564511777660450660.post-47066297644897528772008-07-23T13:01:00.000-06:002008-07-23T13:01:00.000-06:00ajay, the performance impact is relatively small, but noticeable over slow connections and connections with high latency. The ga.js file (previously called urchin.js) is served with gzip compression enabled and is about 9.1K after compression (22.7K without it). The file is served with the Cache-Control header with a value for max-age which appears, in many cases, to prevent the file from being fetched again.<BR/><BR/>The JavaScript request used for tracking is made after all the rest of the page has been loaded. When browsing sites across the internet, I have noticed times where the page load is halted while "Waiting for google-analytics.com..." but my home connection is quite slow.mndrixhttp://www.blogger.com/profile/00943372190551332722noreply@blogger.comtag:blogger.com,1999:blog-2564511777660450660.post-69399713550351828812008-07-20T22:17:00.000-06:002008-07-20T22:17:00.000-06:00I'm curious about the performance impact of Google Analytics as I'm thinking about doing it for some iPhone web sites.<BR/><BR/>How big is urchin.js? Is it cached? If so, is it cached across site (ie, if the user got a cached copy of urchin.js form some other site and then visits our site, is he required to download it again).<BR/><BR/>Does the server request issued by the JS occur after the user sees the page? Can I make the JS download after the page is shown, so the user's experience is not impacted by the tracking? (some gprs connections are very very slow, and the latency to connect to a new server is very high, ~2 seconds.)<BR/><BR/>sorry for all the questions, but let me know if you've looked into this, otherwise i'll investigate.ajaynoreply@blogger.comtag:blogger.com,1999:blog-2564511777660450660.post-53292731741328740732007-11-05T07:44:00.000-07:002007-11-05T07:44:00.000-07:00Yes Akshay, Google Analytics returns a 1px square image. If you use Firefox and load the <A HREF="http://livehttpheaders.mozdev.org/" REL="nofollow">LiveHTTPHeaders</A> extension, you can watch the request headers. You could also read the source code of Google's urchin.js That's the file linked to when installing Analytics on a website.mndrixhttp://www.blogger.com/profile/00943372190551332722noreply@blogger.comtag:blogger.com,1999:blog-2564511777660450660.post-40498585364887418082007-11-04T06:52:00.000-07:002007-11-04T06:52:00.000-07:00Most other packages send a request for a dummy 1pixel by 1pixel image and then capture the analytics details. Does Google Analytics too work in the same way? Is there a way to figure this out?Akshayhttp://www.blogger.com/profile/11269189624398951693noreply@blogger.com