sql server - MS-SQL 2012 Principle "Freeze" -
yesterday had "freeze" of 1 of our customers mirrored database. the symptom applications freezed. there no high cpu (~1% sql server , ~10% total) / memory (4gb free ) / disk (50gb free) utilisation. i tried accessing principle-database microsoft sql server management studio. when tried open tables section application freezed well. i stopped whole server , applications switched automatically mirror-database , continued if nothing happened. after (re)starting stopped sql-server resume mirroring without problem. i tried find information in windows events, except messages stopped server , resulting messages mirror became principle, there no failure event. also our applications access database did not report issues. as additional information (i don't know if it's of importance): have got job running backups database full backup every hour , differential backup every 15 minutes (the diff backups go bak file created full backup). backup files overwritten af