LINQED.NET

Application Monitors may hurt performance badly

I’ve just spent two days and a night between them on the client site, trying to solve a severe performance problem with the application, that Netwise (the company I work for) has developed. It is an ASP.NET web application, running on Windows 2008 R2 with IIS 7.5 on a 4-CPU/8G machine. We’ve fine-tuned every possible IIS and ASP.NET setting, defined data caching, output caching, profiled almost every line of the code, however, the application still ran very badly, even when tested with 50 concurrent...

Exceptions are common enemies of Web Apps performance

Yes, exceptions are one of most common sources of performance issues of any .NET application, and especially of ASP.NET Web Applications. Without going into details, every thrown exception, either handled or not, introduces a serious penalty on the code execution time. Consider the following two simplistic functions: private static int Divide( int a, int b) { if (b == 0 ) return int .MaxValue; return a / b; } private static int DivideEx( int a, int b) { try { return a / b; } catch (DivideByZeroException...

ASP.NET Validators Common Misconception

There is a common misconception regarding ASP.NET validators among many ASP.NET developers, even seasoned ones. Many developers think that by adding a validator to a form and associating it to a control will guarantee the validity of that control’s value. They are SO wrong! Try the following: Create a new form with a Textbox, Required field validator and a Button. Associate the Validator with the Textbox, and set its ErrorMessage property to anything you want: < div > < asp : TextBox ID...

Canceling AJAX Web Service call

There are times you need to develop a data-entry web form calling and AJAX-enabled web service to perform some complex computations that must be done on the server (for example, when a database access needed to do the computation). The computation is sometimes based on numerous data-entry fields, so when a change in one of the fields has occurred, you want to send a web service request to re-compute the data. As a most simple example, I’ll create a form that is capable of doing an extremely difficult...