The sys.dm_db_log_space_usage DMV is a new DMV for SQL Server 2012. It returns Total Size, Used Size, and Used Percent size for a transaction log file of a given database. To illustrate this DMV, I will query the DMV against my AdventureWorks2012 database.
SELECT * FROM sys.dm_db_log_space_usage
As mentioned above, the result set gives us the total size of the transaction log in bytes, the used size of the log in bytes, and the percent of the log that has been used.
This is a very simplistic DMV but returns valuable information. Being able to detect when a transaction log is close to being full is always a valuable thing to alert on, and this DMV just provided an additional method for acquiring the necessary information.
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