Hello,
Hopefully someone can bring some light to the topic "What is sys.dm_tran_database_transactions really showing".
I know there are some articles about this dmv, but if you dig some deeper they don't solve my question...
Scenario:
SQL Server 2012, database recovery model set to simple, ldf size=25GB
Problem:
ldf is running out of space - so I want to find the responsible process(es). If I query something like...
select session_id
, database_transaction_log_bytes_used
, database_transaction_log_bytes_reserved
, database_transaction_log_bytes_used_system
, database_transaction_log_bytes_reserved_system
from sys.dm_tran_database_transactions as A inner join sys.dm_tran_session_transactions as B on a.transaction_id=B.transaction_id
where db_name(A.database_id)='myDatabase'
... I get a total amount of ~10MB used. dbcc sqlperf(logspace) confirms, the 25 GB ldf file is 99% used.
I noticed the same behavior with the TempDB log file.
sys.databases shows log_reuse_wait_desc ACTIVE_TRANSACTION
Question:
Can someone please explain what transactions will be shown in sys.dm_tran_database_transactions and why I cannot see the really huge transactions?
Thank you for your help!