[BUG] Memory usage grows continuously #2619
Description
I have an application (newest LiteDB version) where I never close my LiteDatabase instance because I need continuous read access:
public ILiteCollection<EmailMessage> Messages { get; }
// ctor:
Messages = _db.GetCollection<EmailMessage>("messages");When changing folders in the UI, I query messages like this:
return _repository.Messages
.Find(m => m.AccountId == Folder.Folder.AccountId && m.FolderPath == Folder.Folder.Path)
.OrderByDescending(m => m.DateSent);The following problems arise:
- LiteDB internal objects (pages, cache, etc.) continuously grow in memory.
- Memory usage can reach even more than 1 GB.
- No/very little memory is released while the database remains open.
If I instead open, query, and immediately dispose of the database for each operation, memory is released. There doesn’t seem to be a way to limit LiteDB’s cache when keeping the DB open long-term.
There should be a configurable limit to LiteDB’s internal cache when the DB is kept open. Also, memory should not grow unbounded during read-only access.
This seems like it might be related to the internal page caching system. I’m unsure if the intended usage is to always open/dispose for each query, or if there should be a better way to manage long-lived read-only access.