Adaptively estimating a read access time to a second track based upon the binned radial position of the second track within a rotating media storage device
View Patent ↗A rotating media storage device (RMSD) to adaptively estimate a read access time to a second track based on the radial position of the second track is disclosed. The RMSD includes a disk having at least a first track and a second track and a microprocessor for controlling operations in the RMSD including seek operations. During a seek operation, the microprocessor bins a radial position of the second track and estimates a read access time to the second track based on the binned radial position of the second track.
1. In a rotating media storage device (RMSD) connectable to a host computer, the RMSD having a disk including at least a first track and a second track, a moveable head, a cache memory and a microprocessor for controlling operations in the RMSD including seek operations and read caching algorithms for read operations that include pre-read operations and post-read operations, a method of efficiently switching between a read operation on the first track and a read operation on the second track, the method comprising the steps of:
a. binning a radial position of the second track;
b. estimating a read access time to the second track based on the binned radial position of the second track and the distance between the first track and the second track; and
c. modifying a read caching algorithm based on the estimated read access time.
2. The method of claim 1 , wherein binning comprises grouping outer diameter track bands and inner diameter track bands.
3. The method of claim 2 , wherein the outer diameter track bands and the inner diameter track bands are uniform.
4. The method of claim 2 , wherein the outer diameter track bands and the inner diameter track bands are non-uniform.
5. The method of claim 1 , wherein modifying the read caching algorithm comprises adjusting the amount of post-read performed on the first track.
6. The method of claim 5 , wherein the amount of post-read performed on the first track is decreased if the second track belongs to an outer diameter track band.
7. The method of claim 5 , wherein the amount of post-read performed on the first track is increased if the second track belongs to an inner diameter track band.
8. The method of claim 5 , wherein the amount of post-read performed on the first track is inversely proportional to the binned radial position of the second track.
9. The method of claim 1 , wherein modifying the read caching algorithm comprises adjusting at least one of the amount of post-read performed on the first track or the amount of pre-read performed on the second track.
10. A rotating media storage device (RMSD) connectable to a host computer, the RMSD comprising:
a disk including at least a first track and a second track;
a moveable head;
a cache memory; and
a microprocessor for controlling operations in the RMSD including seek operations and read caching algorithms for read operations that include pre-read operations and post-read operations, the microprocessor under the control of a program to,
a. bin a radial position of the second track;
b. estimate a read access time to the second track based on the binned radial position of the second track and the distance between the first track and the second track; and
c. modifying a read caching algorithm based on the estimated read access time.
11. The RMSD of claim 10 , wherein binning a radial position of the second track comprises grouping outer diameter track bands and inner diameter track bands.
12. The RMSD of claim 11 , wherein the outer diameter track bands and the inner diameter track bands are uniform.
13. The RMSD of claim 11 , wherein the outer diameter track bands and the inner diameter track bands are non-uniform.
14. The RMSD of claim 10 , wherein modifying the read caching algorithm comprises adjusting the amount of post-read performed on the first track.
15. The RMSD of claim 14 , wherein the amount of post-read performed on the first track is decreased if the second track belongs to an outer diameter track band.
16. The RMSD of claim 14 , wherein the amount of post-read performed on the first track is increased if the second track belongs to an inner diameter track band.
17. The RMSD of claim 14 , wherein the amount of post-read performed on the first track is inversely proportional to the binned radial position of the second track.
18. The RMSD of claim 10 , wherein modifying the read caching algorithm comprises adjusting at least one of the amount of post-read performed on the first track or the amount of pre-read performed on the second track.
19. A computer system comprising a host computer and a rotating media storage device (RMSD), thc RMSD further comprising:
a disk including at least a first track and a second track;
a moveable head;
a cache memory; and
a microprocessor for controlling operations in the RMSD including seek operations and read caching algorithms for read operations that include pre-read operations and post-read operations, the microprocessor under the control of a program to,
a. bin a radial position of the second track; and
b. estimate a read access time to the second track based on the binned radial position of the second track and the distance between the first track and the second track; and
c. modifying a read caching algorithm based on the estimated read access time.
20. The computer system of claim 19 , wherein binning a radial position of the second track comprises grouping outer diameter track bands and inner diameter track bands.
21. The computer system of claim 20 , wherein the outer diameter track bands and the inner diameter track bands are uniform.
22. The computer system of claim 20 , wherein the outer diameter track bands and the inner diameter track bands are non-uniform.
23. The computer system of claim 19 , wherein modifying the read caching algorithm comprises adjusting the amount of post-read performed on the first track.
24. The computer system of claim 23 , wherein the amount of post-read performed on the first track is decreased if the second track belongs to an outer diameter track band.
25. The computer system of claim 23 , wherein the amount of post-read performed on the first track is increased if the second track belongs to an inner diameter track band.
26. The computer system of claim 23 , wherein the amount of post-read performed on the first track is inversely proportional to the binned radial position of the second track.
27. The computer system of claim 19 , wherein modifying the read caching algorithm comprises adjusting at least one of the amount of post-read performed on the first track or the amount of pre-read performed on the second track.