Hitachi Global Storage Technologies Netherlands B.v.

International Business Machines Corporation

Hitachi Global Storage Technologies B.v.

Hget Netherlands B.v.

Richard M H New

Jorge Campello De Souza

Spencer W Ng

Donald Joseph Molaro

Bruce Alexander Wilson

Anand Kulkarni

Damien C D Le Moal

Marco Sanvido

Mason Lamar Williams

Frank R Chu

Chunqi Han

Zvonimir Z Bandic

Cyril Guyot

Daniel James Colegrove

Martin Aureliano Hassner

Motoyasu Tsunoda

Prakash Kasiraj

George Anthony Dunn

Brian Harry Marcus

Frank Rui-Feng Chu

Brian H Marcus

A system for enhancing command scheduling is provided. In particular embodiments, the system includes a processor and a scheduler that receives commands from the processor for accessing a storage device. The scheduler receives a set of commands, some of which have a deadline, and the scheduler is configured to determine an execution order for those commands. The scheduler is also configured to defer the execution of one or more of those commands to a later time.

Adaptive command scheduling

A data storage device encrypts data stored in non-volatile memory using a bulk encryption key. The data storage device uses a key derivation function to generate an initial encryption key. The data storage device then wraps an intermediate encryption key with the initial encryption key and stores the wrapped intermediate key in the non-volatile memory. The data storage device wraps the bulk encryption key with the intermediate encryption key and stores the wrapped bulk encryption key in the non-volatile memory. The data storage device can unwrap the wrapped intermediate key to generate the intermediate encryption key using the initial encryption key. The data storage device can unwrap the wrapped bulk encryption key to generate the bulk encryption key using the intermediate encryption key. The data storage device decrypts data stored in the non-volatile memory using the bulk encryption key.

Techniques for encrypting data on storage devices using an intermediate key

Data is written to a hard disk drive using shingled writing principles, i.e., each data track is partially overwritten when an immediately contiguous data track is written. One or more contiguous data tracks establish a band, and a band establishes a respective segment in a log-structured file system.

Log-structured file system for disk drives with shingled writing

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.

Disk drive with nonvolatile memory for storage of failure-related data

Techniques for optimizing hard disk drive performance. According to one embodiment, a storage system includes a storage unit that stores data and a controller. The controller receives an idle mode indication and performs at least one operation based on the idle mode indication. According to another embodiment, a host system includes a processor and a scheduler that is operative to issues commands. The processor computes the idle mode indication, and the processor sends the idle mode indication to the storage system.

Using idle mode prediction to improve storage system performance

The invention is a storage device which implements a write barrier command and provides means for a host to designate other write commands as being sensitive or insensitive to the existence of write barrier commands. The device can optimize the execution of commands by changing the order of execution of write commands that are insensitive to write barrier command. In an embodiment of the invention a flag associated with the write command indicates whether the command is sensitive or insensitive to the existence of write barrier commands. In an embodiment of the invention the write barrier command can be implemented as a write command with a flag that indicates whether the command is a write barrier command. In one embodiment of the invention the queue of commands and data to be written to the media is stored in a non-volatile cache.

Storage device with write barrier sensitive write commands and write barrier insensitive commands

Embodiments of the present invention recite a method of preserving data on a hard disk drive. In one embodiment, a first copy of data is read from at least one sector of a hard disk drive and stored in a first location. A second copy of the data is stored in a non-volatile memory location of the hard disk drive. The first copy of the data is then modified to create a modified copy. The second copy of the data is then used to verify that the modified copy of data has been correctly written to the at least one sector of the hard disk drive.

Micro-journaling of data on a storage device

A verifiable security mode is provided for securing data on a storage device, such as a hard disk drive. When the verifiable security mode is enabled, only authenticated accesses to data stored on the storage device are permitted after entering a password. An end user is prevented from disabling the verifiable security mode. The verifiable security mode can be set to allow or disallow an administrator from disabling the verifiable security mode. The verifiable security mode can be implemented, for example, in firmware on a hard disk drive (HDD).

Techniques for providing verifiable security in storage devices

Enhancements to the functionality of a file system are provided. A file system can provide an additional level of error correction, in addition to the error correction provided by a data storage device. An extension to the metadata area in a file system can store index information about data files that the file system can use to reduce the time it takes to access the files. A file system can use extended metadata to store conditional access information for data files stored in the file system. A data storage device can also examine and characterize the data being stored in order to categorize a user's files automatically. Modules can be loaded into a file system to provide new functionality to the file system. The modules can load additional modules to extend their functionality.

Techniques for enhancing the functionality of file systems

A storage system that stores verify commands for all the write commands requiring verification in a verify-list that will be processed as a background task is described. The verify-list can include coded data fields that flexibly designate selected alternative states or possibilities for how and where the user data is actually stored. Alternatives for the verify-list include storing the actual raw data, no data, the data in compressed form, a CRC type signature of the data and/or a pointer to a backup copy of the data that is stored either in non-volatile memory such as flash memory or on the disk media in a temporary area. In case of a verification error in various alternative embodiments the user data can be recovered using the backup copy in the verify-list in the write cache, the backup copy in flash memory or on the disk, or from the host.

Storage system and method for opportunistic write-verify

Embodiments of the present invention recite a method of preserving data on a hard disk drive. In one embodiment, a copy of data is read from at least one sector of a hard disk drive and stored in a memory location of the hard disk drive. At least a portion of the data in the memory location of the hard disk drive is then replaced to create a modified copy of data. A copy of the modified copy of data is then stored in a non-volatile memory location of the hard disk drive. Finally, the data from the at least one sector is replaced with the modified copy of data.

A system for enhancing the reliability of file systems is provided. In particular embodiments, the system includes a data storage device that includes one or more journal blocks, one or more primary metadata blocks, and one or more mirror metadata blocks. The system also includes a file system that writes metadata to the one or more journal blocks before writing the metadata to both the one or more primary metadata blocks and to the one or more mirror metadata blocks.

Techniques for improving the reliability of file systems

Data is written to a hard disk drive using shingled writing principles, i.e., each data track is partially overwritten when an immediately contiguous data track is written. Two or more contiguous data tracks establish a band, and a band may store data from one and only one file, such as an AV file.

System and method for writing data to dedicated bands of a hard disk drive

A hybrid disk drive, i.e., a disk drive with two types of permanent storage media (conventional disk media and nonvolatile memory, such as flash memory), uses its nonvolatile memory in operational modes other than the power-save or 'standby' mode wherein the disks are spun down. In a first additional mode, called a 'performance' mode, one or more blocks of write data are destaged from volatile memory (the disk drive's write cache) and written to the disk and simultaneously one or more data blocks of write data are destaged from the volatile memory and written to the nonvolatile memory. In a second additional mode, called a &#x201c;harsh-environment&#x201d; mode, the disk drive includes one or more environmental sensors, such as temperature and humidity sensors, and the nonvolatile memory temporarily replaces the disks as the permanent storage media. In a third additional mode, called a &#x201c;write-inhibit&#x201d; mode, the disk drive includes one or more write-inhibit detectors, such as a shock sensor for detecting disturbances and vibrations to the disk drive. In write-inhibit mode, if the write-inhibit signal is on then the write data is written from the volatile memory to the nonvolatile memory instead of to the disks.

Growing community of inventors

San Jose, CA, United States of America

Richard M H New