The Oracle database recovery time after a failover is directly proportional to the number of outstanding transactions and the size of the database. The following parameters control database recovery time:
To minimize recovery time, set the previous parameters to relatively low values. Note that excessively low values adversely impact performance. Try different values to find the optimal value.
Oracle provides additional tuning parameters that control the number of database transaction retries and the retry delay time. Be sure that these values are large enough to accommodate the failover time in the cluster environment. This ensures that failover is transparent to database client application programs and does not require programs to reconnect.