|Product:||Syniti Replicate, DBMoto|
|Summary:||Reduce the size of the SQL Server transaction log to improve replication times during mirroring and avoid timeout errors|
The size of the transaction log in SQL Server could slow down the read of the log during mirroring, or even cause a SQL timeout error when attempting to retrieve information from the log. Note that if a timeout error occurs during synchronization, you need to restart the replications with an initial refresh to avoid losing data.
The SQL Server transaction log grows normally as more and more transactions keep being sent to the server. Typically a database administrator performs regular database backups (BACKUP LOG << db_name>> WITH TRUNCATE_ONLY) to save the status of the database at specific points in time and save a copy in case of disasters. The backup operation, as a side effect, automatically reduces the size of the transaction log by removing the part consisting of transactions already completed. An alternative to the backup is the log truncate operation, which has the same effect of truncating the log content (but recovery will not be possible because no backup of the database is available).
To reduce the physical size of the transaction log, you also need to compact its content by running a log shrink operation (DBCC SHRINKFILE), which will compact the unused space inside the log file (something similar to a defrag operation on your hard drive).
The database administrator usually develops a plan for managing database backups and the associated log file. However, if you are experiencing problems with log size in Syniti Replicate/DBMoto, you can reduce the size of the transaction log by performing a manual backup and shrinking the log file.