Building a Web 2.0 Portal with ASP.NET 3.5

Chapter 6. Optimizing ASP.NET AJAX

Just like other frameworks, the ASP.NET AJAX Framework is not capable of serving all of the specific needs for every type of Ajax application. Frameworks are kept simple and generic enough to satisfy 70 percent of the Ajax application’s requirements. But the remaining 30 percent of requirements require you to go deep into the framework to make the necessary modifications. Moreover, off-the-shelf Ajax frameworks don’t solve all real-life problems, and new and unique challenges always come up every now and then. In this chapter, we will review several challenges posed by Ajax applications that must be resolved for high-volume Ajax web sites. There are also several design decisions that must be made if you release it as a mass consumer Ajax web site.

Combining Multiple Ajax Calls into One Call

Network roundtrip is the most expensive part of Ajax applications. You need to do everything you can to reduce the number of calls made to the server. Because each call has the overhead of connecting to the server and then downloading the response, each call wastes some time on the network. When you have five calls going to the server within a short time for some particular operation, you are wasting about one second (assuming 200 ms network latency) on the network. So, a popular practice among Ajax developers is to batch multiple consecutive single calls into one large call. This saves the network roundtrip as there’s only one network roundtrip to do, and thus ...