Patent ID: 6839804

Claim:
A disk array storage device with a plurality of logical storage devices, the disk array storage device processing transactions with multiple tasks of different categories to be performed in different ones of the logical storage devices, said disk array storage device comprising: A) means for processing the tasks according to their respective positions of corresponding task requests in a task request queue, B) means for assigning priority to one of the logical storage devices, and C) means for receiving a task request from any of the logical storage devices including: i) category determining means for determining the task category and the logical storage device related to the task request, ii) first transfer means for transferring a task request of a first category to a position in the task request queue having a first priority, iii) second transfer means for transferring a task request of a second category related to the one logical storage device to a position in the task request queue having a second priority that is less than the first priority, and iv) third transfer means for transferring any other task request to a position in the task request queue of a third priority that is less than the second priority.