The tempdb in our production (SQL Server 2005) environment keeps growing (reached 200GB last week), but the most of the space (99%) is free. "sys.dm_db_file_space_usage" shows that most page allocation happened in internal_object_reserved_page_count. Why will SQL server grow the tempdb while there's plenty of free space in it ?
We have a farm of web servers connecting to the db server with a fixed service account. Connection pooling is used by ADO.NET.
We don't mind the SQL server use the tempdb, the real problem is that the server keep growing the tempdb without considering how much free space in it.