Disk drive deferring refresh based on environmental conditions
View Patent ↗A disk drive is disclosed including a disk having a plurality of tracks, and a head actuated over the disk. A refresh monitor is maintained for refreshing data stored on the disk. A need for a refresh operation is detected when the refresh monitor exceeds a first threshold, wherein the refresh operation is deferred based on an environmental condition.
1. A disk drive comprising:
a disk comprising a plurality of tracks;
a head actuated over the disk; and
control circuitry operable to:
maintain a refresh monitor operable to refresh data stored on the disk; and
when the refresh monitor exceeds a first threshold:
perform the refresh operation when an environmental condition falls within a predetermined range; and
defer the refresh operation when the environmental condition is outside the predetermined range.
2. The disk drive as recited in claim 1 , wherein the control circuitry is further operable to:
adjust the refresh monitor in response to the environmental condition; and
refresh the data in response to the adjusted refresh monitor.
3. The disk drive as recited in claim 1 , wherein the environmental condition comprises an ambient temperature.
4. The disk drive as recited in claim 1 , wherein the environmental condition comprises a vibration.
5. The disk drive as recited in claim 1 , wherein the environmental condition comprises an altitude.
6. The disk drive as recited in claim 1 , wherein the control circuitry is further operable to:
maintain a history of the environmental condition; and
adjust the refresh monitor based on the history of the environmental condition.
7. The disk drive as recited in claim 6 , wherein the control circuitry evaluates the history of the environmental condition to determine whether to defer the refresh operation.
8. The disk drive as recited in claim 7 , wherein the control circuitry evaluates the history of the environmental condition to determine how long to defer the refresh operation.
9. The disk drive as recited in claim 1 , wherein the control circuitry is further operable to force the refresh operation when the refresh monitor exceeds a second threshold.
10. The disk drive as recited in claim 1 , wherein the control circuitry is further operable to abort the refresh operation based on the environmental condition.
11. The disk drive as recited in claim 1 , wherein the disk comprises a plurality of refresh zones, and the control circuitry is further operable to maintain a refresh monitor for each refresh zone.
12. A method of operating a disk drive, the disk drive comprising a disk including a plurality of tracks, and a head actuated over the disk, the method comprising:
maintaining a refresh monitor operable to refresh data stored on the disk; and
when the refresh monitor exceeds a first threshold:
performing the refresh operation when an environmental condition falls within a predetermined range; and
deferring the refresh operation when the environmental condition is outside the predetermined range.
13. The method as recited in claim 12 , further comprising:
adjusting the refresh monitor in response to the environmental condition; and
refreshing the data in response to the adjusted refresh monitor.
14. The method as recited in claim 12 , wherein the environmental condition comprises an ambient temperature.
15. The method as recited in claim 12 , wherein the environmental condition comprises a vibration.
16. The method as recited in claim 12 , wherein the environmental condition comprises an altitude.
17. The method as recited in claim 12 , further comprising:
maintaining a history of the environmental condition; and
adjusting the refresh monitor based on the history of the environmental condition.
18. The method as recited in claim 17 , further comprising evaluating the history of the environmental condition to determine whether to defer the refresh operation.
19. The method as recited in claim 18 , further comprising evaluating the history of the environmental condition to determine how long to defer the refresh operation.
20. The method as recited in claim 12 , further comprising forcing the refresh operation when the refresh monitor exceeds a second threshold.
21. The method as recited in claim 12 , further comprising aborting the refresh operation based on the environmental condition.
22. The method as recited in claim 12 , wherein the disk comprises a plurality of refresh zones, and further comprising maintaining a refresh monitor for each refresh zone.
23. A disk drive comprising:
a disk comprising a plurality of tracks;
a head actuated over the disk;
a means for maintaining a refresh monitor operable to refresh data stored on the disk; and
when the refresh monitor exceeds a threshold:
a means for performing the refresh operation when an environmental condition falls within a predetermined range; and
a means for deferring the refresh operation when the environmental condition is outside the predetermined range.