Sign Up to our social questions and Answers Engine to ask questions, answer people’s questions, and connect with other people.
Login to our social questions & Answers Engine to ask questions answer people’s questions & connect with other people.
Lost your password? Please enter your email address. You will receive a link and will create a new password via email.
Please briefly explain why you feel this question should be reported.
Please briefly explain why you feel this answer should be reported.
Please briefly explain why you feel this user should be reported.
I’ve read that merging several multiple javascript files into a single file improves performance, is that true?
If so, is there an easy and error-free way of merging them, or perhaps an online-tool that automatically does that?
Many thanks.
See Multiple javascript/css files: best practices? and Supercharging Javascript in PHP.
The short answer is that you want to minimize external HTTP requests. The best way to do that is to force the browser to cache files you server until they change. You do this by versioning the files and providing a far future Expires header. When the filename changes (by changing the version) the browser will get the new version.
If you do this then multiple Javascript files don’t really matter. But if you force the client to download 27 JS files on each and every page with no caching then reducing the number of files can make a substantial difference. Of course this is still inferior to effective caching/versioning strategies.
Another more recent issue to consider is iphone caching:
So in some circumstances combining files can be detrimental.