DISK DRIVE WITH NONVOLATILE MEMORY FOR STORAGE OF FAILURE-RELATED DATA

• US 20080130156A1
• Filed: 09/13/2006
• Published: 06/05/2008
• Est. Priority Date: 09/13/2006
• Status: Active Grant

• Current Assignee: Western Digital Technologies Incorporated (Western Digital Corporation)
• Original Assignee: Hitachi Global Storage Technologies Netherlands BV (Western Digital Corporation)
• Inventors: Chu, Frank R., Dunn, George A., Ng, Spencer W., New, Richard M.H.
• Granted Patent: US 8,015,433 B2
• Time in Patent Office: Days
• US Class Current: 360/71
• CPC Class Codes: G11B 20/18 Error detection or correction; Testing , e.g. of drop-outs

Abstract

A disk drive that includes nonvolatile memory monitors the drive'"'"'s reliability-related parameters to detect real or potential failure events, and records failure-related data in nonvolatile memory, rather than in reserved areas of the disks. The monitoring may be by running a diagnostic routine or by regular or periodic monitoring of disk drive sensors, like temperature and shock sensors. The failure events to be monitored and recorded may include defective data sectors. When a new defective sector is detected after the disk drive has been put into operation, that defective sector is taken out of service and its logical block address (LBA) is mapped to a memory space in the nonvolatile memory rather to a reserved spare sector on the disk. When a read or write command is received for an LBA range that includes the defective sector'"'"'s LBA, the defective sector is skipped while the whole LBA range of the command is processed and the user data for the defective sector'"'"'s LBA is read from or written to the mapped memory space in the nonvolatile memory.

Claims

1. A disk drive comprising:

a rotatable recording disk for the storage of user data from a host computer;

a controller for writing user data to and reading user data from the disk; and

nonvolatile memory connected to the controller;

wherein the controller includes logic for executing method acts comprising;

determining a disk drive failure-related event and recording failure-related data representative of said event in the nonvolatile memory.

2. The disk drive of claim 1 wherein the method act of determining a failure-related event comprises measuring the value of a disk drive parameter and detecting when said measured value exceeds a predetermined threshold, wherein said parameter is selected from the group consisting of temperature, frequency of errors in reading data, and time for the disk to reach its operating speed.

3. The disk drive of claim 1 wherein the disk drive includes a temperature sensor connected to the controller and wherein the method act of determining a failure-related event comprises monitoring a signal from the temperature sensor and detecting when said temperature signal exceeds a predetermined threshold.

4. The disk drive of claim 1 wherein the disk drive includes a shock sensor connected to the controller and wherein the method act of determining a failure-related event comprises monitoring a signal from the shock sensor and detecting when said shock signal exceeds a predetermined threshold.

5. The disk drive of claim 1 wherein the disk includes concentric data tracks, each data track including a plurality of sectors for the storage of data, each sector having a logical block address (LBA) readable by the controller, wherein determining a disk drive failure-related event comprises determining that a sector is defective, and wherein recording failure-related data in the nonvolatile memory comprises storing in the nonvolatile memory user data for said defective-sector LBA.

6. The disk drive of claim 5 wherein all of the sectors in each data track have an associated LBA and none of the sectors are reserved as spare sectors to replace defective sectors.

7. The disk drive of claim 1 wherein the disk drive includes volatile memory connected to the controller and wherein the controller further comprises logic for executing method acts of, in a standby mode of operation wherein the disk is not rotating, transferring user data from the host computer to the volatile memory and then destaging said user data from the volatile memory to the nonvolatile memory.

8. A magnetic recording disk drive comprising:

a rotatable magnetic recording disk for the storage of user data from a host computer, the disk having a plurality of concentric data tracks, each data track including a plurality of contiguous sectors for the storage of user data, each sector having an associated logical block address (LBA);

a read/write head movable across the surface of the disk for writing user data to the sectors and reading user data from the sectors;

a controller adapted for connection to the host computer for transferring user data between the host computer and the sectors on the disk in response to read and write commands from the host computer;

volatile memory connected to the controller for temporary storage of user data; and

nonvolatile memory connected to the controller; and

wherein the controller comprises logic for executing method acts of;

determining that a sector is defective;

assigning to the LBA for said defective sector a memory space in the nonvolatile memory; and

in response to a command from the host computer to write user data associated with said defective sector'"'"'s LBA, writing the user data to said assigned memory space.

9. The disk drive of claim 8 wherein the controller further comprises logic for executing the method act of, in response to a command from the host computer to read user data associated with said defective sector'"'"'s LBA, reading the user data from said assigned memory space.

10. The disk drive of claim 8 wherein the controller further comprises logic for executing method acts of, in a standby mode of operation wherein the disk is not rotating, transferring user data from the host computer to the volatile memory and then destaging said user data from the volatile memory to the nonvolatile memory.

11. The disk drive of claim 8 wherein all of the sectors in each data track have an associated LBA and none of the sectors are reserved as spare sectors to replace defective sectors.

12. The disk drive of claim 8 wherein the nonvolatile memory comprises flash memory.

13. The disk drive of claim 8 wherein the volatile memory comprises DRAM.