OracleConnection也是有Connection pool的吧
The .NET Framework Data Provider for Oracle provides connection pooling automatically for your ADO.NET client application. You can also supply several connection string modifiers to control connection pooling behavior (see "Controlling Connection Pooling with Connection String Keywords," later in this topic).
来自:http://msdn.microsoft.com/en-us/library/ms254502(v=vs.110).aspx