Hi there,

This afternoon our hosting company claimed that the CPU usage for the server hosting our site went through the roof and as a result they had to restart our application pool. Below is the error log information they were able to give us.

Any ideas?

DNN: 5.4.1
AS: 1.5.3

Thanks,
Donovan

Exception information:
Exception type: ArgumentOutOfRangeException
Exception message: Index was out of range. Must be non-negative and less than the size of the collection.
Parameter name: index

Request information:
Request URL: http://www.siteurl.com/DesktopModul...PortalId=0
Request path: /DesktopModules/activesocial/cb.ashx
User host address: 123.123.123.123
User: username@siteurl.com
Is authenticated: True
Authentication Type: Forms
Thread account name: servername\I_site

Thread information:
Thread ID: 12
Thread account name: servername\I_site
Is impersonating: True

Stack trace: at System.Collections.ArrayList.get_Item(Int32 index)
at System.Collections.Specialized.NameObjectCollectionBase.BaseGet(Int32 index)
at System.Collections.Specialized.NameValueCollection.Get(Int32 index)
at System.Collections.Specialized.NameValueCollection.get_Item(Int32 index)
at Active.Modules.Social.cbhandler.ProcessRequest(HttpContext context)
at System.Web.HttpApplication.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute()
at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)

First idea, upgrade. Not sure if that will make any difference, but you are running several releases behind.

Second, if I recall correctly, you were having performance issues with your site even before Active Social was completely configured. The request you provide above does nothing more than poll the server every 2 minutes. The only way I could see this request crashing any server would be if an authenticated user came up with a hack to mimic the request several times per second.

What I think really happened, something else was pegging your processor, the host restarted the app pool, then the code above tried to execute during the app restart (or immediately after), but failed because Active Social treated it as a hack attempt.

DNN without serious attention to caching and compression can do horrendous things to CPU. Out of the box settings are notoriously bad; with Active Social integrated, it could be easy to see it as the culprit when in reality some significant tuning is needed.