Hi folks, I am trying to get some info about these types of locks and how they behave from performance point of view in SQL2005. At the moment what I know is that BULKOP_BACKUP_DB can appear when you: 1) Do what described in BOL, i.e. a backup 2) Have insufficient disk space in the db file and have autogrow option set to ON and your server is trying to get more space. 3) Do a bulk insert But it is certainly something else: at the moment I see a lot of them in tempdb on one of my production servers and it only appear under a heavy load. And there is no active backups, no autogrow settings and no bulk inserts into tempdb...so what can cause those types of locks ?