Tuning for Fast Recovery

Review the database layout, runtime configuration, and the data space accounting setting to reduce recovery time.

• Database layout – Databases should have logs and data on their own physical devices. The access patterns for log and data are different and should be kept separate. Configure the underlying I/O subsystem to handle concurrent I/O requests from multiple databases in SAP ASE.
• Runtime configuration – Configure an optimal housekeeper wash percentage controlled by housekeeper free write percent, so that during free cycles dirty pages are written out. The default value is usually optimal.

  Ensure that long-running transactions are kept to a minimum. Long- running transactions hold resources and can also cause longer recovery times. To avoid longer recovery times, using polite shutdown to shut down the server.

• Setting space accounting – If data space accounting is not essential for a database, set the database option to turn off free space accounting using sp_dboption. This disables threshold actions on the data segment