CONTROL APPARATUS, STORAGE DEVICE, AND TIMEOUT-POSSIBILITY NOTIFYING METHOD
A magnetic disk device performs test write on a test cylinder to check the state of each head before system information is stored in disks. The magnetic disk device then determines the state of each head based on the test write results stored in a test-write-result table. When a head is defective, the magnetic disk device notifies a host of the possibility of the occurrence of a timeout as a fault prediction.
1 . A control apparatus comprising:
a head test unit that performs, before system information is stored in a storage medium of a storage device, a test to check state of heads of the storage device; and
a host notifying unit that notifies, when a head among the heads is determined as defective based on a result of the test by the head test unit, a host that the head is defective.
2 . The control apparatus according to claim 1 , wherein the head test unit checks the state of the heads by performing test write on a test cylinder, which is a predetermined area on the storage medium, and, when an error occurs in the test write, the head test unit performs test write on another test cylinder to check again the state of the heads.
3 . The control apparatus according to claim 1 , further comprising a system-information storing unit that stores the system information in the storage medium with, among the heads, a head in a state determined as normal based on the result of the test.
4 . The control apparatus according to claim 3 , wherein when the system information cannot be stored in the storage medium, the system-information storing unit stores the system information in a memory.
5 . The control apparatus according to claim 3 , wherein when the system-information storing unit cannot store the system information in the storage medium, the head test unit checks the state of the heads.
6 . A storage device comprising:
a head test unit that performs, before system information is stored in a storage medium, a test to check state of heads; and
a host notifying unit that notifies, when a head among the heads is determined as defective based on a result of the test by the head test unit, a host that the head is defective.
7 . A timeout-possibility notifying method comprising:
performing, before system information is stored in a storage medium of a storage device, a test to check state of a head of the storage device; and
notifying, when the head is determined as defective based on a result of the test, a host that the head is defective.