Data storage device sorting access commands based on performance and off-track mitigation optimization
Various illustrative aspects are directed to a data storage device, method, and one or more processing devices that are configured to: select a seek time model from a plurality of seek time models based at least in part on an operational characteristic of an access command, the operational characteristic relating to an off-track susceptibility of executing the access command; determine an access time for the access command using the selected seek time model; and select a next access command for execution based on the determined access time for the access command and determined access times for other ones of a plurality of access commands.
1. A data storage device, comprising:
one or more disks;
an actuator mechanism configured to position a selected head among one or more heads proximate to a corresponding disk surface of a corresponding disk among the one or more disks; and
one or more processing devices configured to:
select a seek time model from a plurality of seek time models based at least in part on an operational characteristic of an access command, the operational characteristic relating to an off-track susceptibility of executing the access command;
determine an access time for the access command using the selected seek time model; and
select a next access command for execution based on the determined access time for the access command and determined access times for other ones of a plurality of access commands.
2. The data storage device of claim 1 , wherein the plurality of seek time models comprises:
an original seek time model; and
at least one slow seek time model based on the original seek time model and at least one delay time model.
3. The data storage device of claim 2 , wherein the operational characteristic comprises the off-track susceptibility of a seek access pattern comprising the access command and an access command preceding the access command.
4. The data storage device of claim 3 , wherein the selecting the seek time model comprises one of:
selecting the at least one slow seek time model in response to the access command being a write seek with a seek length shorter than a first threshold, preceded by a read seek with a seek length longer than a second threshold; and
selecting the original seek time model in response to the access command not being (1) a write seek with a seek length shorter than the first threshold or (2) a command preceded by a read seek with a seek length longer than the second threshold.
5. The data storage device of claim 4 , wherein the selecting the at least one slow seek time model reduces a likelihood of an off track write event with the access command.
6. The data storage device of claim 3 , wherein the selecting the seek time model comprises one of:
selecting the at least one slow seek time model in response to the access command being a write seek with a seek length shorter than a first threshold, preceded by a track following with a following time shorter than a second threshold, preceded by a read seek with a seek length longer than a third threshold; and
selecting the original seek time model in response to the access command being a write seek with a seek length shorter than the first threshold, preceded by a track following with a following time longer than the second threshold, preceded by a read seek with a seek length longer than the third threshold.
7. The data storage device of claim 2 , wherein the at least one slow seek time model comprises:
a first slow seek time model comprising the original seek time model combined with a first delay time model; and
a second slow seek time model comprising the original seek time model combined with a second delay time model different than the first delay time model.
8. The data storage device of claim 7 , wherein:
the first delay time model is based on a first status of tilt distance learning; and
the second delay time model is based on a second status of tilt distance learning different than the first status of tilt distance learning.
9. The data storage device of claim 2 , wherein in response to determining that a rotational distance of the access command is less than a time determined using the at least one slow seek time model:
the selecting the seek time model comprises selecting the original seek time model; and
the determining the access time comprises adding a time of one revolution to a time determined using the original seek time model.
10. The data storage device of claim 9 , wherein:
the operational characteristic comprises a piezoelectric (PZT) actuator stroke; and
the selecting the seek time model comprises selecting the slow seek time model in response to the PZT actuator stroke exceeding a threshold.
11. The data storage device of claim 10 , wherein the selecting the at least one slow seek time model optimizes usage of the PZT actuator stroke.
12. The data storage device of claim 1 , wherein the determining the access time for the access command using the selected seek time model comprises adjusting the selected seek time model based on drive temperature.
13. The data storage device of claim 1 , wherein the determining the access time for the access command using the selected seek time model comprises adjusting the selected seek time model based on drive voltage.
14. The data storage device of claim 1 , wherein rotational positioning optimization circuitry performs the selecting the seek time model, the determining the access time, and the selecting the next access command.
15. A method comprising:
selecting, by one or more processing devices, a seek time model from a plurality of seek time models based at least in part on an operational characteristic of an access command, the operational characteristic relating to an off-track susceptibility of executing the access command;
determining, by the one or more processing devices, an access time for the access command using the selected seek time model; and
selecting, by the one or more processing devices, a next access command for execution based on the determined access time for the access command and determined access times for other ones of a plurality of access commands.
16. The method of claim 15 , wherein:
the plurality of seek time models comprises: an original seek time model; and at least one slow seek time model based on the original seek time model and at least one delay time model; and
the operational characteristic comprises one of: the off-track susceptibility of a seek access pattern comprising the access command and an access command preceding the access command; and a piezoelectric (PZT) actuator stroke.
17. The method of claim 15 , wherein the determining the access time for the access command using the selected seek time model comprises adjusting the selected seek time model based on drive temperature or drive voltage.
18. One or more processing devices comprising:
means for selecting a seek time model from a plurality of seek time models based at least in part on an operational characteristic of an access command, the operational characteristic relating to an off-track susceptibility of executing the access command;
means for determining an access time for the access command using the selected seek time model; and
means for selecting a next access command for execution based on the determined access time for the access command and determined access times for other ones of a plurality of access commands.
19. The one or more processing devices of claim 18 , wherein:
the plurality of seek time models comprises: an original seek time model; and at least one slow seek time model based on the original seek time model and at least one delay time model; and
selecting the at least one slow seek time model reduces a likelihood of an off track write event with the access command.
20. The one or more processing devices of claim 18 , wherein:
the plurality of seek time models comprises: an original seek time model; and at least one slow seek time model based on the original seek time model and at least one delay time model; and
selecting the at least one slow seek time model optimizes usage of a piezoelectric (PZT) actuator stroke.