Need to understand why this riverpod implementation could cause memory leak

[thanhdatvo]

Hi,
Currently our product is using riverpod but it freezes after sometimes due to memory leaks or memory bloating.

Example of our riverpod implementation:

class UserStore {
  final String instanceId;


  // A static cache to store instances
  static final Map<String, UserStore> _cache = {};

  // Factory constructor to implement caching
  factory UserStore(String instanceId) {
    // If the user with the given ID already exists, return it
    if (_cache.containsKey(instanceId)) {
      print("Returning cached instance for ID: $instanceId");
      return _cache[instanceId]!;
    }

    // Otherwise, create a new instance and cache it
    final user = UserStore._internal(instanceId);
    _cache[instanceId] = user;

    return user;
  }

  // Private named constructor for internal object creation
  UserStore._internal(this.instanceId);

  // Method to clear cache if needed
  static void clearCache() {
    _cache.clear();
  }

  @override
  String toString() => 'UserStore(instanceId: $instanceId)';

   final userNameProvider = Provider<String>((ref) => '');
   final userAgeProvider = Provider<int>((ref) => 0);
}

According to this document, https://riverpod.dev/docs/essentials/do_dont#avoid-dynamically-creating-providers
These could cause some memory leaks.

Could anybody help explain whether it actually causes any memory leak or memory bloating, if the number of UserStore instances is limited by the factory?

[rrousselGit]

Deleting an entry from _cache would not cause UserStore. userNameProvider/userAgeProvider to be garbage collected.

[thanhdatvo]

@rrousselGit
Thank you for you very quick reply.
I have another question.
Does the approach below have the same behavior as the above? Will it cause a memory leak or memory bloating with multiple instance generated? Is there any manual way to clean them if they are not in use?

 final userNameProvider = Provider.family<String, String>((ref, instanceId) => '');
 final userAgeProvider = Provider.family<String, int>((ref, instanceId) => 0);