Question

When checking the System.Net.ServicePointManager.DefaultConnectionLimit in .Net 4 in my debugger, I see really high numbers. I see 24 on one machine and see 48 on another machine.

This is even the case for a newly created ASP.NET MVC 3 project without any configuration changes done to it. Is this a bug? The documentation clearly states that the default is 2:

The maximum number of concurrent connections allowed by a ServicePoint
object. The default value is 2.

From http://msdn.microsoft.com/en-us/library/system.net.servicepointmanager.defaultconnectionlimit(v=VS.100).aspx

The DefaultNonPersistentConnectionLimit and DefaultPersistentConnectionLimit fields are more realistic 4 and 2, respectively, but the DefaultConnectionLimit number seems out of range.

Answer 1

It’s not a bug. It’s propably 12 per CPU.

The value comes from <connectionManagement> in your Web.config or Machine.config. If neither of files contains element it’s probably configured by autoConfig=True setting at <processModel> element.