Website Loading Time

He Team,

I have developed website using sitefinity version 4.1 Sp2. Our website is live now the issue I am facing is website loading time. The website is loading time is some what slow and some time it takes around 30 sec or more to open home page although website is not much complex with many controls and data.

I am using Yslow to check the performance of website and found some of the javascript  files which automatically loads by sitefinity framework and are heavy in KBs. Can I stop this script files from loading and if yes then does it make any problem to my website?

Also let me know any specific tips which needs to follow to improve performance of website. Couple of things I know like reduce the requests and compress the files etc.

Regards,

Jesse Sanchez

Hello Jesse,

Thank you for contacting us.

The scripts Sitefinity loads automatically are javascript references to Telerik.WebResource.axd and Telerik.ScriptResource.axd. This files are necessary they contain the scripts that widgets placed on pages use for their specific functionality. Also rad scripts for RadControls are there too. On the first page load the whole Telerik.WebResource.axd is loaded and it size is big because it contains all the scripts for all pages you use on your pages. When you then browse trough different pages you will see this resource size may vary in size. This is because from all scripts loaded the first time each page is using just a part. Sitefinity loads all scripts by default because of script combining. Script combining sends all scripts in a single server request rather than separate request for each script needed.
You can turn off script combining in Administration->Settings->Advanced->Pages->ScriptCombining = False.
This is not recommended because the request will slow the performance on visitors`s computers.

I have some tips that may prove useful in reducing the load time.
Enable caching for the whole content of the site. Sitefinity caching is enabled by default so If you have not made changes to this you should be having it.

Make sure the server you are hosting at has enough ram to support the cache and the initial load from visitors. See if you have restriction on the amount of ram you can use.

If you database is at a distant location this will slow the performance.
Set static files expiration in IIS to a different value so that static files are not loaded every time from your project folder in order to be sent to the requesting client. I suppose this is the main slowing factor in your case. If you are using a lot of static images they should be requested from cache.
Also you can check with firebug`s net tab to see if images are slowing the load. Images should be loading 6 at a time(default settings for Firefox) other 6 images are waiting in blocking. Here is a very good explanation on several topics why blocking occurs. The blocking appears to be caused by simultaneous loading of many items and the browser allows only a certain ( 6 for Firefox) at a time. Observing other websites it appears to be a common scenario when many resources have to be loaded

If you are referencing some scripts from url`s they will definitely slow your site because a request will be made to the distant url for every user until the script contents are cached because javascript is executed at the client. Try loading this script asynchronously to prevent it from slowing the performance.

As performance gets better when the site gets visited and the corresponding loads are lower it may be a good option to write a crawler that will visit your site at some time interval in order to prevent the first user performance hit. Here is a sample tutorial + complete code of a web crawler.

You can also refer to this documentation on optimizing performance.

Greetings,
Stanislav Velikov
the Telerik team