Unless your page loads really slowly, I've found that the javascript delay is almost non-existent.
On Monday, November 7, 2011 8:06:57 AM UTC-5, Lasse Reichstein wrote: > > The defer attribute tells the browser that the script doesn't have to > be run immediately (i.e., it doesn't use document.write). That means > that it can start fetching the script immediately when it sees the > script tag *and* continue parsing the document. > > Without the defer attribute, the browser must stop parsing the > document until the script has completed loading and been run, because > the script might use document.write to change how the parsing should > continue. > > If you put the script at the end of the body, the browser won't start > fetching it until it has parsed the script tag. That introduces an > extra delay before the script is ready and run - the time it takes to > parse the document and create the DOM for it. > > By putting the script tag early but with the defer attribute can > reduce the latency of your page - the time it takes before the onload > event fires - by fetching over the network (or even from local cache), > which is I/O bound, while it parses the document (which is memory/CPU > bound). > > But then, AFAIK, not all browsers handle the defer attribute the way > it was intended, so it's no panacea. > > /L > > > -- To view archived discussions from the original JSMentors Mailman list: http://www.mail-archive.com/[email protected]/ To search via a non-Google archive, visit here: http://www.mail-archive.com/[email protected]/ To unsubscribe from this group, send email to [email protected]
