ADONETpooler

ADONETpooler is a term used to describe the connection pooling mechanism implemented by ADO.NET providers. It is not a separate product but the component that manages the lifecycle of database connections to improve performance by reusing existing connections instead of creating and destroying them for every request.

ADONETpooler operates primarily within the ADO.NET provider layer and is typically organized per distinct connection string. Each provider maintains its own pool for connections that share the same connection string, including data source, database, credentials, and provider-specific options. When a consumer closes or disposes a connection, the physical connection is returned to the pool rather than being closed, allowing subsequent requests to reuse it. If no pooled connection is available and the pool has not reached its maximum size, a new physical connection may be opened. Connections may be pruned after periods of inactivity according to provider settings.

Configuration and behavior are largely controlled by the connection string. Pooling can usually be enabled or disabled with a Pooling parameter, and additional options such as Min Pool Size, Max Pool Size, Connection Lifetime, and Connection Timeout influence how aggressively connections are kept alive, reused, or discarded. Defaults and exact semantics vary by provider, but pooling is typically enabled by default in many ADO.NET data providers.

Usage considerations include ensuring that connections are always closed or disposed to return them to the pool, as leaks can exhaust resources. Because pooling is keyed by connection string, changing credentials or certain properties creates a new pool. Improper tuning can lead to server load or resource contention, especially in high-concurrency scenarios. See also ADO.NET, SqlClient, and general connection pooling concepts.