.net core high cpu utilization , Perfview can not get ntdll!?

Question

currently our .net core app is using 100% cpu utilization with really small troughput, after using perfview it just show ntdll!?, also all my threads contian the same class that cannot be resolved ( even after symbol lookup).

Have someone else experienced this?

Answer 1

I also see "ntdll!?" in lot of my Perview snapshots. All of them don't have any CPU stack traces but other info which is not helpful. Most of the time, CPU traces are under some other name and not in "ntdll!?"

You can collect more Perfview snapshots these suggestions below:

1. Make sure you have latest version of PerfView from github
2. Check on 'CPU Samples' checkbox if not already checked
3. Look at the right process ID (PID) for your application
4. In Perfview output, open Advanced Group --> Processor Stacks. It shows you stacks running in different processes
5. Use 'Thread Time" check box to get extra information like any blocking operation