Whilst installing an update package on the client’s/customer’s development environment the ASP.NET worker process would be killed suddenly. This issue was found on Sitecore 8.1 Update 4.
There was nothing shown in the Sitecore log or in the windows Event log. Therefore I took a Memory dump and investigated the dump using Debug Diagnostic 2 . I found at the bottom of the report 100000’s of lines with the same 4 lines of text, so I assumed there was an infinite loop, which was responsible for using all the memory, and crashing the ASP.NET worker process.
I could not reproduce the error in a clean installation of Sitecore, so I assumed it was due to configuration and or some solution specific code. So I started making a comparison between the customers solution and the clean sitecore and I identified that the following settings where defined twice:
showconfig.aspx confirmed this as you can see below.
The first was caused by an error in the solution specific configuration, the remaining were caused by 2 Sitecore includes having the same setting.
Ensure no settings and or other configuration is duplicate. Typically after I found out what the error was I discovered that Sitecore writes a warning in the log file! Maybe I should pay more attention to warnings.
Anyway I hope this helps 🙂