Improving Performance for Backup and Restore

The overall time it takes to complete a backup or restore a database depends largely on the strategy you choose for mixing full and incremental restores.

Several other factors also affect the speed of backup and restore operations: the number of archive devices, data verification, the memory available for the backup, and size of the IQ and catalog stores.

• Increasing the Number of Archive Devices
  The TO clause in the BACKUP statement controls the number of archive devices.
• Eliminating Data Verification
  You can also improve the speed of backup and restore operations by setting CRC OFF in the BACKUP command.
• Spooling Backup Data
  You may find that it is faster and more efficient to create backups on disk, and then spool them onto tape for archival storage. If you choose this approach, you need to unspool the data onto disk before restoring it.
• Increasing Memory Used During Backup
  The amount of memory used for buffers during backup directly affects backup speed, primarily for tape backups. The BLOCK FACTOR parameter of the BACKUP command controls the amount of memory used. If your backups are slow, you may want to increase the value of BLOCK FACTOR for faster backups.
• Balancing System Load
  SAP Sybase IQ allows you to perform backups concurrently with all other read/write operations, except those that affect the structure of the database.
• Controlling the Size of the Catalog Store
  an SAP Sybase IQ database consists of an IQ store and an underlying catalog store.