Introduction to ASP.Net App Suspend in Visual Studio 2013


Microsoft revealed the final version of Visual Studio 2013 last month. There are various new ASP.NET features and Web Tools also revealed with the release of Visual Studio 2013. Some of them are: ASP.NET Scaffolding, ASP.NET MVC 5, ASP.NET SignalR, Entity Framework 6 and ASP.NET App Suspend.

In that context, this article explains the new ASP.NET App Suspend in Visual Studio 2013.


Microsoft released the game-changing feature with this ASP.NET App Suspend in the .NET 4.5.1 Framework. It thoroughly transforms the experience of the user and economic model for hosting large members that use ASP.NET Web Sites on a single machine.

ASP.NET App Suspend is the brand new feature that is used to make the website responsive and also facilitate more site hosting on a single machine. Commercial Web hosters will definitely like it. It is built on top of other new features in the Windows Server 2012 R2 called Internet Information Services (IIS) Idle Worker Process Page-Out that is the new modification in IIS. It is the basic .NET implementation of the IIS feature.

It is a self-tuning mechanism for web hosting like CLR GC generations. There are basically the following three states of the addition of suspend:

  •  Inactive Sites
  • Active Sites
  • Suspended Sites


The site is inactive at initially. It is activated when a user makes a request for the site. The site is loaded into memory and becomes active. When the site becomes idle, it will be suspended. The memory of suspended sites is used to open and load new sites. However the suspended sites are kept in a state from which the site can resume quickly. With this three-state model in place, Windows Server 2012 R2 can deliver consistent performance for many more ASP.NET sites, hosted in a shared hosting environment.

Enable and Monitor ASP.NET App Suspend

If you want to enable the Idle Time-out Action as Suspend, it is very easy. You just need to modify the settings of IIS Manager configuration. The following is the screenshot of the IIS settings.

iis configuration

Hosting Usage Scenarios

The following scenarios benefit from the ASP.NET App Suspend:

  • Shared Hosting

    The companies that are using or selling shared hosting, now can load more sites on a given machine and the sites are more responsive.
  • Switch to Hosting

    If the owners of a web site want to benefit from low-cost shared hosting, they can get it and also deliver a responsive experience of the website.
  • Hot spare for Large Sites

    Large high-traffic sites can maintain spares in suspend, ready for when one of the servers behind a load balancer goes down, whether it is planned or unplanned.


This article has introduced you to the new features revealed with the release of Visual Studio 2013. It provides much better responsiveness for the website that do not get consistent traffic. Thanks for reading.