Track down memory leak in WPF

Question

Hi

Context: We are building a framework for rapid delivery of WPF applications. This framework uses Autofac as an IoC container and also uses regions from Prism v1. We are scheduling tasks with Parallel extensions from Microsoft.

We are facing the following problem: When we boot the application with empty views (so just a shell with regions and placeholder controls), the memory will remain stable for about 60 seconds and after that it will increase about every second with 4kb, then 4kb, after that 8kb. So every 3 seconds we have 16Kb added to our memory pressure.

What have we tried to track down the leak. I started out by using dotTrace but I couldn't see any difference between 2 snapshots taken 30 minutes apart. Moved on to .NET memory profiler because it gives me more information but again we cannot see any differences between 2 snapshots. We can see that a number of objects get created but they are removed too and results in a delta of 0. So I moved on to windbg but the result is the same.

Another weird thing is that when we start sysinternals dbgvw we don't see any calls being made in our applications.

Do you have any suggestions of what we might try next to find out what/who is the culprit?

Answer 1

If you are looking for unmanaged leaks and are using visual studio you can get surprisingly helpful information using the built in crt functions:

see an answer to a related question

Answer 2

As it turns out it was a bug inside WPF and the workaround was to create a window handler as very first object or something. Thanks guys