# Optimizing Performance This article summarizes the most important resources and tips and tricks you can use to improve the performance of your project. ## Blog Posts The **Optimization Tips** series in the Telerik blog includes the following blog posts: * [Optimization Tips: Testing Page Performance](http://telerikwatch.com/2008/05/optimization-tips-testing-page.html) * [Optimization Tips: The Rad Managers for ASP.NET AJAX](http://telerikwatch.com/2008/04/optimization-tipsthe-rad-managers-for.html) * [Optimization Tips: Using RadAjaxManagerProxy Controls](http://telerikwatch.com/2008/05/optimization-tips-using.html) * [Optimization Tips: Using HTTP Compression](http://telerikwatch.com/2008/05/optimization-tips-using-http.html) * [Optimization Tips: Optimizing Custom Skins](https://blogs.telerik.com/ToddAnglin/Posts/08-06-24/Optimization_Tips_Optimizing_Custom_Skins.aspx) ## Tips and Tricks By default, each Telerik control serves a set of files (JavaScript code and stylesheets) that are needed for proper client-side operation and rendering. When loading a page with several controls on it, the number of these files can become very large, often resulting in a reduced page load time and increased traffic. The reason for this problem is that browsers make separate requests to the server for each of these resources. Usually, this problem is overcome by disabling the automatic script and stylesheet serving the controls, combining them into a smaller set of files and manually registering the links to these files in the page. This approach is not the best for a number of reasons: * You must extract the files from the assembly for each control release. * Files become too large to be maintainable or you have to write a script to merge the source files. * The number of the merged files you need to maintain can become very large depending on the control sets you have on different pages. Nevertheless, by using the [ScriptManager](https://www.telerik.com/products/aspnet-ajax/documentation/controls/scriptmanager/overview) and the [StyleSheetManager](https://www.telerik.com/products/aspnet-ajax/documentation/controls/stylesheetmanager/overview) controls, you can use dragging and dropping to achieve the combination of resources to a single request. You need to add a [ScriptManager](https://www.telerik.com/products/aspnet-ajax/documentation/controls/scriptmanager/overview) to your page instead of the default ScriptManager and the JavaScript files will get combined into a single file. Additionally, including the [StyleSheetManager](https://www.telerik.com/products/aspnet-ajax/documentation/controls/stylesheetmanager/overview) in the page makes the stylesheet requests combined into a single request. Both controls need an HttpHandler to be declared in the application configuration file to operate properly. To add the handler, use the **Smart Tags** of the controls. The ScriptManager and the StyleSheetManager controls also enable you to download the resources the Telerik controls need from the Telerik CDN instead of using WebResource requests. To do that, set their `CdnSettings-TelerikCdn` property to `Enabled`. For more information, refer to the [CDN Overview](https://www.telerik.com/products/aspnet-ajax/documentation/controls/scriptmanager/cdn-support/overview) article. Using the CDN takes load off your server and improves resource caching. Downloading from the CDN, however, will result in a request for each individual file (script, stylesheet, font, and so on). You can improve the CDN performance even further by instructing the controls to fetch a combined resource of all scripts and base stylesheets for all the controls in a single request by toggling the `Telerik.ScriptManager.TelerikCdn.CombinedResource` and `Telerik.StyleSheetManager.TelerikCdn.CombinedResource` [`appSettings` keys](https://www.telerik.com/products/aspnet-ajax/documentation/getting-started/installation/web-config-settings-overview) to `enabled`. This configuration is exposed for an individual instance through the `CdnSettings-CombinedResource` property. It is important to test the performance only when debugging is disabled. Set `` in the web.config. When it is true, the MS AJAXdebugging code causes a severe performance hit on the client-side. The fact that most of the editor functionalities implemented in JavaScript, thus resulting in 10 times slower performance compared to native compiled code. The following table lists Telerik UI for ASP.NET AJAX controls and the resources for their performance optimization. | Controls | Solutions for Performance Optimization | | :------------------------ | :----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | Grid | | | Editor | | | TreeView | [Optimizing the TreeView performance](https://www.telerik.com/products/aspnet-ajax/documentation/controls/treeview/troubleshooting/optimizing-radtreeview-performance) | | Captcha | [Disabling the Captcha audio to eliminate requests to the built-in audio handler](https://www.telerik.com/products/aspnet-ajax/documentation/controls/captcha/troubleshooting/optimize-application-performance-disable-audio) | | ComboBox | [Optimizing the Combobox performance](https://www.telerik.com/products/aspnet-ajax/documentation/controls/combobox/troubleshooting/optimizing-the-combobox) | | Menu | [Optimizing the Menu performance](https://www.telerik.com/products/aspnet-ajax/documentation/controls/menu/performance/optimizing-radmenu-performance) | | TabStrip | [Optimizing the TabStrip performance](https://www.telerik.com/products/aspnet-ajax/documentation/controls/tabstrip/performance/optimizing-radtabstrip-performance) | | Pickers | | | Inputs and TextBoxes | Performance problems can be caused by using inputs and textboxes in templates of list controls. A better idea is to create an outside edit form similar to the one demonstrated in the [Client-side edit, update, delete and insert with Controls for ASP.NET AJAX, WebServices and LINQ](https://www.telerik.com/blogs/client-side-edit-update-delete-and-insert-with-radcontrols-for-asp-net-ajax-webservices-and-linq) article. | | ToolTip | [Optimizing the ToolTip performance](https://www.telerik.com/products/aspnet-ajax/documentation/controls/tooltip/performance/optimizing-radtooltip-performance) | | Scheduler | [Optimizing the Scheduler performance](https://www.telerik.com/products/aspnet-ajax/documentation/controls/scheduler/performance/optimizing-radscheduler-performance) | | HtmlChart | [Optimizing the HtmlChart performance](https://www.telerik.com/products/aspnet-ajax/documentation/controls/htmlchart/troubleshooting/performance-optimizations) | | AjaxPanel and AjaxManager | [Optimizing performance by using the AjaxManager](https://www.telerik.com/products/aspnet-ajax/documentation/controls/ajaxmanager/performance-optimization) |