| name | dart-memory |
| description | Manage memory efficiently in Dart and Flutter apps to prevent leaks and reduce GC pressure. Use when disposing resources, handling large assets, optimizing image caching, or profiling allocation patterns. |
| metadata | {"platforms":"cross-platform, mobile","languages":"dart","category":"optimization"} |
Memory Management
Mobile devices have limited RAM. Efficient memory management is critical to prevent crashes and ensure a smooth user experience.
Resource Lifecycle
- Explicit Disposal: Always close
StreamController, Timer, FocusNode, and ChangeNotifier in the dispose() method.
- Late Initialization: Use
late to delay object creation until it's actually needed, reducing initial memory footprint.
Garbage Collection (GC) Pressure
- Generational GC: Dart's GC is optimized for short-lived objects. However, creating thousands of objects in a single frame can still cause jank.
- Object Re-use: Avoid creating new objects in
build() or high-frequency loops. Reuse data structures where possible.
- Large Collections: Clearing a large list (
list.clear()) is better than re-assigning it to a new list if the list itself is long-lived.
Mobile Specifics
- Isolates: Use
Isolate.run() for heavy computations (JSON parsing > 1MB, image processing). This keeps the main thread free and prevents UI freezes.
- Image Memory: Use
cacheWidth and cacheHeight in Image.network or Image.asset to avoid loading high-resolution images into memory at full size.
- Memory Leaks: Use the DevTools Memory View to identify "leaking" objects that stay in the heap after their context (like a screen) is closed.
Large Data Handling
- Pagination: Never load entire datasets into memory. Use server-side or local database pagination (Isar, SQLite).
- Streaming: For large files or real-time data, use
Stream to process data in chunks rather than buffering the entire content in memory.
