In Sharepoint 2013 when installed the Configuration Database recovery model is set to full, what people doesnt know is that this setting can have a negative effect on your disk space, whatever operation you do in sharepoint configuration will be written to this log, and the advantage of this recovery model is that you can get back to any point in time, however the disadvantage is that it will use a lot of space.
The last time I had to fix this on a customer, the log was 67GB, and the only way the noticed is because their disk was almost full and operations were becoming very slow.
The way to fix it, its with this script which will change the recovery model to simple, and also shrink the DB file.
USE MTP_RC_DB; -- Connect to the database that you want to shrink ALTER DATABASE MTP_RC_DB SET RECOVERY SIMPLE; -- Set the recovery model to SIMPLE CHECKPOINT; -- Issue a CHECKPOINT to purge out the inactive transactions DBCC SHRINKFILE (MTP_RC_DB_LOG, 5); -- Shrink the transaction log file to a reasonable size ALTER DATABASE MTP_RC_DB SET RECOVERY FULL; -- Set the recovery model back to FULL
That should fix the issue described at the beginning of this post.
On this page on technet, there are the best practices regarding Sharepoint Databases: read here