Some of the database recovery enhancements made to Adaptive Server version 12.5.1 include:
Log I/O size – Adaptive Server uses the largest buffer pool available in the default data cache for log I/O. If a pool with the largest buffer size is not available, the server creates this pool dynamically, and uses the pool for log I/O. The buffers for this pool come from the default pool. Recovery tunes the size of the large buffer pool for optimal recovery performance. Also, if the large pool is available but the size is not optimal, Adaptive Server dynamically resizes it and the default pool for optimal recovery performance. The buffer pool configurations are restored at the end of recovery.
For more information on the largest buffer pool, pool sizes, and sp_poolconfig commands, see the Performance and Tuning Guide.
async prefetch limit – during recovery, the server automatically sets the local async prefetch limit for the pools in the default data cache used by recovery to an optimal value. This overrides any user specifications for the duration of recovery.
When recovery completes, the original configuration values are restored.
