I have a SQL Server 2005 SP2 system with a single database that is 42gigs in size.

It is a modestly active database that sees on average 25 transactions per second.

The database is configured in Full recovery model and we perform transaction log backups every hour. However it seems to be pretty random at some point during the day the log backup will go from it's average size of 15megs all the way up to 40gigs.

There are only 4 jobs that are scheduled to run on the SQL server and they are all typical backup jobs which occur on a daily/weekly basis.

I'm not entirely sure of what client activity takes place as the application servers are maintained by a different department.

Is there any good way to track down the cause of these log file growths and pinpoint them to a particular application, or client?

Thanks in advance.