无法使用ANTS RedGate Memory Profiler解决内存泄漏问题

Question

we are developing a WPF application using Prism 4 and are experiencing serious memory leaks because of resources not being released. We are using ANTS Memory Profiler to detect which classes are preventing the garbage collector from freeing the memory, but we are very new to this tool, so our understanding of its output is limited.

Our test case consists in opening a window that lets you choose a plugin from a list. The window hosts a Wizard control that contains a header, a set of buttons and a main area that displays the active WizardPage (that is a UserControl). By choosing a plugin and clicking the Next button, more WizardPage controls are registered in the Wizard Region and added to the Wizard.Pages collection using a RegionAdapter. The user can then move through the pages by clicking the Next/Previous buttons. If we open the Wizard window and just click the Cancel button, the Wizard control finalizer is called as expected. However, if we open the Wizard window and expand the plugins ComboBox before clicking the Cancel button, then the Wizard control finalizer is never called. Here is a screenshot of the Instance Categorizer for Wizard in ANTS Memory Profiler:

We tried almost everything with no success, could someone help us to understand what's going on here?

Thank you in advance.

Answer 1

If you're just starting out with ANTS Memory Profiler , you might find it most useful to start by looking at the class list instead of the instance categorizer .

A good approach would probably be to start by taking a baseline snapshot before clicking the Next button in your application. Then open the Wizard Window and expand the plugins combobox, then click Cancel. At that point, take another memory snapshot in ANTS, and compare the two. If you go into the class list , you'll probably see an instance of the WizardPage class which exists in memory now which didn't exist previously and which should have been removed. Select that and then in ANTS go to the instance list .

Select the instance of WizardPage and click to see the instance retention graph , which shows the chains of references back to the GC roots which are holding that specific instance in memory.

By looking back up those chains of references, you should be able to identify which link exists which should be broken in order to free the object from memory.