Timeout from SSRS Report Viewer

I asked about this a few weeks ago and we didn’t get very far.  I have more information that hopefully will help identify the culprit.

My Wise-J application makes extensive use of SSRS.  We’re hosting the ASP.NET ReportViewer control, using a custom wrapper based on https://wisej.com/support/answers/1660/file/215/Wisej.AspNetReportViewer.zip.  We’ve added additional feature to the wrapper to handle setting and reading the report parameters, but otherwise it’s the same control as in the example.

When a user attempts to view a very long running report, the browser appears to “give up”, resulting in a blank pane where the report content should appear.  The “give up” always occurs at 90 seconds.

Back in VWG times, we solved this by setting ScriptManager.AsyncPostBackTimeout to zero in our VWG wrapper control.  Turns out, the default value for Async Post Back Timeout is in fact 90 seconds.  According to an old blog post (which no longer exists) from someone at MSFT, setting the timeout to zero makes the timeout infinite.  Nothing in the documentation mentions this special behavior for zero, but it’s a common convention and it appears to be true.

Making the same change in our AspNetReportViewer control does in fact make a change in behavior – now instead of giving up predictably at 90 seconds, the browser gives up at some “random” time greater than 90 seconds.  We’ve observed times ranging from 2 minutes to over 20 minutes.

Around the same time as the browser stops waiting (I haven’t timed it accurately enough to know more than it’s about the same time), we see the following event show up in the Windows Application Event Log:

Event code: 3001
Event message: The request has been aborted.
Event time: 9/22/2023 9:26:49 AM
Event time (UTC): 9/22/2023 4:26:49 PM
Event ID: 76c91045270044fbae2bf87f054dca58
Event sequence: 85
Event occurrence: 1
Event detail code: 0

Application information:
Application domain: /LM/W3SVC/1/ROOT/My_Application-1-133398733995319542
Trust level: Full
Application Virtual Path: /My_Application
Application Path: C:\…path to my application\
Machine name: LT-DEV4

Process information:
Process ID: 8564
Process name: w3wp.exe
Account name: MyDomain\MyUser

Exception information:
Exception type: HttpException
Exception message: Request timed out.

Request information:
Request URL: http://localhost/My_Application/Wisej.AspNetHost.aspx?sid=74f0253d-01e4-3521-f77b-836bcabd02bd&_cid=id_508&_sc=2
Request path: /My_Application/Wisej.AspNetHost.aspx
User host address: ::1
User:
Is authenticated: False
Authentication Type:
Thread account name: MyDomain\MyUser

Thread information:
Thread ID: 11
Thread account name: MyDomain\MyUser
Is impersonating: False
Stack trace:

Custom event details:

Occasionally the event is slightly different and mentions ReportViewerWebControl.axd?Type=SessionKeepAlive, but most of the events are from Wisej.AspNetHost.aspx.

So, what’s getting the exception?  What timeout is being exceeded?  How can I change that timeout?  Why doesn’t this result in any visible error message?

My Wise-J version is 3.2.3.  I see that the current version is 3.2.5, so I’ll go ahead and upgrade and see if that makes any difference.

-cd