AdvancedDisk disk pool properties

Table: AdvancedDisk disk pool properties describes the disk pool properties.

Table: AdvancedDisk disk pool properties

Property	Description
Name	The disk pool name.
Storage server	The storage server name. The storage server is the same as the NetBackup media server to which the storage is attached.
Disk volumes	The disk volumes that comprise the disk pool.
Total size	The total amount of space available in the disk pool.
Total raw size	The total raw, unformatted size of the storage in the disk pool.
Comment	A comment that is associated with the disk pool.
High water mark	The high water mark is a threshold that triggers image cleanup. NetBackup expires images that are no longer valid until the low water mark is reached. The default is 98%. When an individual disk volume is full, NetBackup chooses a different volume in the pool to write backup images to. When the disk pool is full, NetBackup fails any backup jobs that are assigned to the disk pool storage unit.
Low water mark	When the capacity of the disk pool returns to the low water mark, NetBackup again assigns jobs to the storage unit. Capacity is regained as backup images expire. The low water mark setting cannot be greater than or equal to the high water mark setting. The default is 80%
Limit I/O streams	Select to limit the number of read and write streams (that is, jobs) for each volume in the disk pool. A job may read backup images or write backup images. By default, there is no limit. When the limit is reached, NetBackup chooses another volume, if available. If not available, NetBackup queues jobs until a volume is available. Too many jobs that read and write data may degrade disk performance because of disk thrashing. (Disk thrashing is when the read and write heads move between the cylinders excessively as they seek the data for competing jobs.) Fewer streams can improve throughput, which may increase the number of jobs that complete in a specific time period.
per volume	Select or enter the number of read and write streams to allow per volume. Many factors affect the optimal number of streams. Factors include but are not limited to disk speed, CPU speed, and the amount of memory.