Gets the time to wait before closing unused connections in the pool if the count of all connections exeeds MinPoolSize.
The time (in seconds) to wait. The default value is 15 seconds.
If connection pool contains unused connections for ConnectionLifeTime seconds, the half of them will be closed. If there will be unused connections in a second later then again the half of them will be closed and so on. This strategy provide smooth change of connection count in the pool.
NpgsqlConnection Class | Npgsql Namespace