Professional Microsoft® SQL Server® 2008 Administration

19.11. Log-Shipping Performance

On the primary server, to continue to meet performance requirements while concurrent users are accessing the log-shipping system, consider placing the log-shipping backup directory on a separate disk drive from the database. Backup compression also improves performance. As part of ongoing administration, monitor the I/O performance counters for any bottlenecks (e.g., average queue length higher than two for each physical drive). Do database administration activities such as index defragmentation during a period of lower activity, because depending on the level of fragmentation, the transaction-log file will be larger and take longer to back up, which can affect users. To keep the secondary server more closely in sync with the primary server, maintain shorter transactions.

Log shipping uses the default settings for backup compression on the server. Whether a log is compressed depends on the Backup Compression default setting.

To ensure fast recovery in a role switch, the secondary server should have identical capacity to the primary server. This enables it to stay in sync with the primary server. Also, in a role switch, the secondary server will be able to provide the same performance experience that users expect. Similarly, separate the file copy directory from the database; and, as part of ongoing administration, monitor I/O performance counters. Furthermore, monitor network bandwidth to ensure that there is capacity to move the transaction-log ...