Blocking formats for a disk drive that reduce performance
View Patent ↗A method is disclosed for selecting a format for a disk surface of a disk drive, the disk drive comprising the disk surface, and a head actuated over the disk surface. A first TPI is selected for the disk surface, and then evaluated to determine whether it is compatible with a first target capacity. If the first TPI is not compatible with the first target capacity, then a second TPI is selected for the disk surface wherein the second TPI is less than the first TPI.
1. A method of selecting a format for a disk surface of a disk drive, the disk drive comprising the disk surface, and a head actuated over the disk surface, the method comprising:
writing data to the disk surface;
reading the data to generate a metric;
selecting a first tracks per inch (TPI) for the disk surface in response to the metric;
determining that the first TPI is not compatible with a first target capacity due to a data rate of the disk surface being less than a threshold; and
selecting a second TPI for the disk surface wherein the second TPI is less than the first TPI.
2. The method as recited in claim 1 , further comprising:
selecting a TPI profile across the radius of the disk surface; and
adjusting the TPI profile.
3. The method as recited in claim 1 , wherein the disk drive comprises a plurality of disk surfaces further comprising:
selecting a first TPI for each disk surface;
determining that the first TPI of a respective disk surface is not compatible with the first target capacity due to a data rate of the respective disk surface being less than the threshold; and
selecting the second TPI for the respective disk surface.
4. The method as recited in claim 1 , further comprising:
selecting a second target capacity less than the first target capacity; and
selecting the second TPI relative to the second target capacity.
5. The method as recited in claim 1 , wherein the disk drive comprises a plurality of disk surfaces, further comprising:
selecting a second target capacity less than the first target capacity; and
selecting the second TPI for each disk surface relative to the second target capacity.
6. The method as recited in claim 1 , wherein the metric comprises a bit error rate.
7. A method of selecting a format for a disk surface of a disk drive, the disk drive comprising the disk surface, and a head actuated over the disk surface, the method comprising:
writing data to the disk surface;
reading the data to generate a metric;
selecting a first tracks per inch (TPI) for the disk surface in response to the metric;
determining that the first TPI is not compatible with a first target capacity due to a data rate of the disk surface being less than a threshold; and;
selecting a second target capacity for the disk surface wherein the second target capacity is less than the first target capacity.
8. The method as recited in claim 7 , wherein the disk drive comprises a plurality of disk surfaces further comprising:
selecting a first TPI for each disk surface;
determining that the first TPI of a respective disk surface is not compatible with the first target capacity due to a data rate of the respective disk surface being less than the threshold; and
selecting the second target capacity for the respective disk surface.
9. The method as recited in claim 7 , further comprising selecting a second TPI for the disk surface relative to the second target capacity.
10. The method as recited in claim 7 , wherein the disk drive comprises a plurality of disk surfaces, further comprising selecting a second TPI for each disk surface relative to the second target capacity.
11. The method as recited in claim 7 , wherein the metric comprises a bit error rate.
12. A disk drive comprising:
a disk surface;
a head actuated over the disk surface; and
control circuitry operable to:
write data to the disk surface;
read the data to generate a metric;
select a first tracks per inch (TPI) for the disk surface in response to the metric;
determine that the first TPI is not compatible with a first target capacity due to a data rate of the disk surface being less than a threshold; and
select a second TPI for the disk surface wherein the second TPI is less than the first TPI.
13. The disk drive as recited in claim 12 , wherein the control circuitry is further operable to:
select a TPI profile across the radius of the disk surface; and
adjust the TPI profile.
14. The disk drive as recited in claim 12 , wherein the disk drive comprises a plurality of disk surfaces and the control circuitry is further operable to:
select a first TPI for each disk surface;
determine that the first TPI of a respective disk surface is not compatible with the first target capacity due to a data rate of the respective disk surface being less than the threshold; and
select the second TPI for the respective disk surface.
15. The disk drive as recited in claim 12 , wherein the control circuitry is further operable to:
select a second target capacity less than the first target capacity; and
select the second TPI relative to the second target capacity.
16. The disk drive as recited in claim 12 , wherein the disk drive comprises a plurality of disk surfaces and the control circuitry is further operable to:
select a second target capacity less than the first target capacity; and
select the second TPI for each disk surface relative to the second target capacity.
17. The disk drive as recited in claim 12 , wherein the metric comprises a bit error rate.
18. A disk drive comprising:
a disk surface;
a head actuated over the disk surface; and
control circuitry operable to:
write data to the disk surface;
read the data to generate a metric;
select a first tracks per inch (TPI) for the disk surface in response to the metric;
determine that the first TPI is not compatible with a first target capacity due to a data rate of the disk surface being less than a threshold; and;
select a second target capacity for the disk surface wherein the second target capacity is less than the first target capacity.
19. The disk drive as recited in claim 18 , wherein the disk drive comprises a plurality of disk surfaces and the control circuitry is further operable to:
select a first TPI for each disk surface;
determine that the first TPI of a respective disk surface is not compatible with the first target capacity due to a data rate of the respective disk surface being less than the threshold; and
select the second target capacity for the respective disk surface.
20. The disk drive as recited in claim 18 , wherein the control circuitry is further operable to select a second TPI for the disk surface relative to the second target capacity.
21. The disk drive as recited in claim 18 , wherein the disk drive comprises a plurality of disk surfaces and the control circuitry is further operable to select a second TPI for each disk surface relative to the second target capacity.
22. The disk drive as recited in claim 18 , wherein the metric comprises a bit error rate.