dart-memory

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.