Number of times an I/O-intensive task was switched from an engine because Adaptive Server exceeded a I/O batch limit. However, “Exceeding I/O batch size” reports only the context switches from nonlog I/O batches. Adaptive Server paces disk writes to keep from flooding the disk I/O subsystems during operations that perform large amounts of I/O. For example, the checkpoint task writes a large number of data pages to the disk. Adaptive Server switches off the checkpoint task so it sleeps until the batch of writes completes. Checkpoint then wakes and issues another batch.
Configure batch sizes—both nonlog I/O and log I/O—using the i/o batch size parameter.
By default, the number of writes per batch is set to 100. You may want to increase the number of writes per batch if:
You have a high-throughput, high-transaction environment with a large data cache.
Your system is not I/O bound.
