To identify memory leaks in MvvmCross applications using the Memory Graph tool, you can follow these steps, which are generally applicable to iOS development with Xcode. Although MvvmCross is a cross-platform framework, the Memory Graph tool is specific to iOS development within Xcode.
Using the Memory Graph Debugger
1. Launch Your App with Memory Graph Debugger:**
- Open your project in Xcode and ensure you are in debug mode.
- Go to the Debug menu and select Debug Memory Graph. This will launch your app with the Memory Graph Debugger enabled.
2. Run Through Core Flows:**
- Navigate through your app's core flows, such as opening and closing view controllers, performing actions that involve data binding, and any other critical paths that might involve memory allocation.
- Repeat these flows several times to see if memory usage increases unexpectedly.
3. Take Memory Snapshots:**
- After running through these flows, take a memory snapshot by clicking on the Debug Memory Graph button again. This will pause your app and provide a snapshot of the current memory state.
4. Inspect Memory Snapshots:**
- In the Memory Graph Debugger, you will see a graphical representation of objects in memory as nodes, with relationships between them as edges.
- Look for objects that should not be in memory anymore. For example, if you see multiple instances of a view controller or view model that should have been deallocated, it might indicate a memory leak.
5. Identify Leaked Objects:**
- Click on a node representing an object that should not be in memory. The debugger will show you all references to that object, helping you identify why it is being retained.
- Use the object graph to track down the parent node or object that is keeping the leaked object in memory.
6. Fix the Leak:**
- Once you've identified the source of the leak, review your code to find where the strong references are being held. Common issues include:
- Unreleased event handlers.
- Strong references in view models to views or other objects that should be weak.
- Retain cycles in data bindings.
7. Verify Fixes:**
- After making changes to fix potential leaks, repeat the process of running through core flows and taking memory snapshots to ensure that the memory usage does not increase unexpectedly.
Additional Tools for Cross-Platform Development
While the Memory Graph tool is specific to iOS, for cross-platform frameworks like MvvmCross, you might also need to use platform-specific tools for other platforms:
- Android: Use the Android Profiler or LeakCanary to detect memory leaks.
- Windows (MAUI): Utilize tools like Visual Studio's Diagnostic Tools or third-party libraries like MemoryToolkit.Maui to identify memory leaks.
By combining these approaches, you can effectively identify and fix memory leaks in MvvmCross applications across different platforms.
Citations:[1] https://www.reddit.com/r/dotnetMAUI/comments/1c1qlou/maui_memory_leaks/
[2] https://proandroiddev.com/memory-leaks-in-reactive-android-programming-a4ad2b34466a
[3] https://careersatdoordash.com/blog/ios-memory-leaks-and-retain-cycle-detection-using-xcodes-memory-graph-debugger/
[4] https://www.netguru.com/blog/what-are-ios-memory-leaks-and-how-to-detect-them
[5] https://www.linkedin.com/advice/1/how-can-you-prevent-memory-leaks-mvvm-skills-software-design-hsx1c
[6] https://developer.android.com/studio/profile/memory-profiler
[7] https://github.com/dotnet/maui/wiki/Memory-Leaks
[8] https://forums.developer.apple.com/forums/thread/713062
[9] https://www.tothenew.com/blog/memory-leak-with-memory-graph-debugger/