Hello.

We're experiencing an issue with our production installation that's got us scratching our heads. Randomly our website, built using DNN 8.0.1, starts hogging CPU time  getting to the 90-100% and ~2G memory used. When this happens IIS will stop responding and recycling the app pool does nothing, we have to run IISRESET command. There's no spike in users that triggers it and schedulers run normally and here are no errors in logs/event viewer that we can follow so we created dumps from the w3wp process but can't figure out what's wrong. 

Here is one of the dump summaries we took during on of those times. Any details we can provide that can help solve this feel free to ask.

Any help you can provide is really appreciated. Thanks.

Regards,

João Santos

Hello Sebastian,

We are using our own modules, which may or may not be causing this, but we cannot find any leads as to why or where the problem could be and that's why I've posted here. We've checked the IIS logs and everything seems normal, since this a website with few accesses.

This behavior is not predictable and we have not been able to reproduce it on other environments and we've ran out of ideas...

I want to make a bump for this. I am having the same issue with an instance running 7.4.2. https://www.screencast.com/t/Li1VjW4L...

About 5 months ago we followed the security issue from May of 2016 to remove certain items. This just started in the last week. It seems to be very consistent, plateau spikes. When I login to a site on this instance it causes a spike that I see, but these are not being triggered by an action such as logging in. Any ideas would be helpful. 

I have this one instance running on the server on App Pool v4.0 - Integrated. There are 118GB free so it can't be a space issue. The RAM is pretty consistent between 3 and 4GB.