Thanks for the reply.

I've been doing some reading since this morning to try and understand what is happening.

Initially the log was set up as being 1GB in size with autogrowth set to 128MB. When I came in the office this morning, the log was 35 GB with 99% usage. I couldn't see anything that was running on the server to cause the log to be so full. I ran a manual "Checkpoint" on the tempdb and the log emptied to 20% full. I then shrank it to 5GB and have been monitoring the log usage throughout the day.

What is strange is that despite sizing the log at 1GB on server creation, the VLFs in the log file are sized at over 2GB each. When the log was 35 GB there were 16 VLF all sized equally. I am confused by this since I would have thought the growth settings would have stopped it having such large VLF files. I am thinking due to the large VLF files in the log, transactions are hitting the 70% checkpoint threshold but cannot truncate the log as they are not inactive.

What is also confusing me is that the log is constantly being used. Running dbcc sqlperf(logspace) the percentage used is always increasing despite not much going on on the server. Running

SELECT Name, log_reuse_wait_desc

FROM sys.databases

Shows nothing occurring on the tempdb.

Is there anyway I can see what is writing to the log file?