Microsoft – SQL Server – Database Mirroring – Metadata
Transaction safety is a mirroring-specific database property that determines whether a database mirroring session operates synchronously or asynchronously. There are two safety levels: FULL and OFF.
Full transaction safety causes the session to operate synchronously in high-safety mode
Turning off transaction safety causes the session to operate asynchronously, in high-performance mode.
select @@servername as serverName , db_name(database_id) as databaseName , mirroring_safety_level as safetyLevel from sys.database_mirroring tblDatabaseMirroring where tblDatabaseMirroring.mirroring_guid is not null ;