I had a lock up on one of my databases today. I checked with sp_lock, killed the offensive process, and the lock cleared. In my SQL Profiler trace I then see tons and tons of entries with high durations for the following: exec sp_tables NULL,NULL,NULL,NULL Why would these store procedures be taking so long? The other thing I noticed is the offensive process that I killed had a different T-SQL statement in the Activity Monitor than what was returned in SQL Profiler. It seemed "exec sp_tables NULL,NULL,NULL,NULL" was the cause of the lock-up. Is this something that is done internally in SQL or is it likely the application that we have interfacing with the database?