Stmicroelectronics N.v.

Stmicroelectronics Gmbh

Stmicroelectrics N.v.

Aaron Wade Wilson

Lance R Carlson

Russell B Josephson

Brett Lammers

Wayne Aaron Thorsted

Nicolas C Assouad

Wen Lin

Thomas G Adams

Rodney A Mattison

Glenn Alan Lott

Glen Catalano

Alan Longo

William Morgan Tempero

An extent record for an extent based data buffer that includes a host pointer that links the extent record to a next host extent record of a host extent record set, and a storage device pointer that links the extent record to a next storage device extent record of a storage device extent record set. Also, a system for transferring data between a host and a storage device that includes a data buffer coupled to the host and the storage device, where memory in the data buffer is divided into one or more extents, an extent table associated with the data buffer, where the extent table includes at least one extent record, an LBA chain table coupled to the host and the extent table, and a track section table coupled to the storage device and the extent table.

Data storage and caching architecture

The invention comprises a magnetic disk storage system and comprises method for configuring the magnetic disk storage system. The magnetic disk storage system facilitates write and read operations that compensate for variances that are experienced with magnetic disk storage systems. When writing data to a data sector, the magnetic disk storage system utilizes a phase lock oscillator field that has a length that is specified for that data sector. When reading from a data sector, the magnetic disk storage system utilizes an incremental read delay that has a duration that is specified for that data sector. Data sectors with shorter data sector delay periods can have shorter phase lock oscillator fields than data sectors with larger data sector delay periods. This frees-up memory space and increases the capacity and performance of the magnetic disk storage system.

Data placement variation compensation system

A method, and a system for implementing such method, for use in a magnetic disk storage system for compensating for variation in spin speed of a data storage media from a nominal or design spin speed. The method includes providing the nominal spin speed for the data storage media in the particular magnetic disk storage system and then measuring the actual spin speed of the data storage media. In one preferred embodiment, the spin speed measurement is completed by measuring the time from one servo position field to the next sequential servo position field in a track on the data storage media. Next, the present spin speed variation is determined by comparing the measured spin speed with the nominal spin speed. A correction factor is calculated based on the spin speed error and applied to at least one data transfer parameter, such as channel reference frequency or read/write gate assertion timing, prior to a subsequent data transfer process (i.e., a read or a write operation). The spin speed compensation method may further include verifying that the measured spin speed is within a range of acceptable spin speeds. The range of acceptable spin speeds is determined based on maximum spin speed change rates of the magnetic disk storage system and the most recent measured spin speed. If the measured spin speed is outside this range, the data transfer operation, i.e., a write operation, is stopped to prevent damaging data previously stored on the data storage media.

Method and system for compensation for spin speed variation in a magnetic disk storage device

A method, apparatus, computer implemented method and computer programmed product for recovering data from a split sector associated with an inoperable servo timing mark. Instead of using a servo timing mark to synchronize the read/write head to the spin speed variation of a storage media, the trailing end of the data fragment preceding the inoperable servo timing mark is used as a reference point. After detecting the reference point, the read operation is halted a predetermined delay time after which the read operation is resumed recovering the data from the sector relying on the inoperable servo timing mark.

Disk drive error recovery and defect management method

a firm ware based technique related to managing defective data sector information in a disk drive. Specially, technique provides for a dynamic method by which the number of spare or served alternate sectors and their locations can be allocated in the event defective data sectors exist. One advantage of the present invention exists for certain applications where the capacity and/or configuration of the drive are configured at run time. The present invention also has the advantage of improving performance when accessing &ldquo;grown&rdquo; defects by allowing the block relocation information to be placed physically closer to the location of the defective blocks.

Defective data sector management system

A method and system for laying out and accessing data in a disk drive system. The layout resides in a table in firmware of the disk drive system. The table includes multiple entries or rows, one corresponding to each different area in the disk media. The entry provides information about the range of block addresses in that area including the starting and end block address in the area, and information about the range of physical addresses including the head and the starting and ending cylinder number. A firmware routine finds the appropriate entry in the table and converts the block address to the physical address, or vice versa.

Disk drive block ordering system

Disclosed is a storage media defect management method for use in a storage device that is to be coupled to a computer. The method broadly includes writing data to a storage media of the storage device, the storage media having a plurality of servo fields. Stopping the writing upon detecting an off-track or other servo field error with a particular servo field of the plurality of servo fields. Reallocating a plurality of suspect sectors that may be affected by the off-track or other servo field error detected in the particular servo field. The method then proceeds to resume the writing beginning with a next sector following the plurality of suspect sectors that were reallocated. In a preferred implementation, a number of preliminary checks are preferably performed on the plurality of suspect sectors to ascertain which ones may not be part of the reallocation transfer. However, the plurality of suspect sectors that are reallocated will preferably not be more than a maximum look-ahead number set in accordance with a disk zone that the current track being written lies. In this manner, maximum look-ahead reallocation number can be custom implemented depending on which track of the media the servo error is detected.

Look-ahead reallocation disk drive defect management

A method for maximizing buffer usage in a disk drive system. Control circuitry within the disk drive system tansfers the defective sector list for the disk to a buffer, and places the list in a reserved list area. The size of the defective sector list is then determined and the reserved list area is reduced to a size equal to the size of the defective sector list plus some spare room. If the newly sized reserved list area is not at one end of the buffer, it is then moved to one end of the buffer to leave the remainder of the buffer as a contiguous and expanded reserved user area for use data. The expanded reserved user area reduces the time of read or write operations in a disk drive.

Method for maximizing buffer usage on a disk drive

A method and apparatus for performing head switch operations in a magnetic disk system having a magnetic disk device that is segmented into a plurality of cylinders, which cylinders are grouped into an inner zone, a middle zone, and an outer zone. The inner zone is near the innermost area of the magnetic disk device. The outer zone is near the outermost area of the magnetic disk device. The middle zone is in between the inner zone and the outer zone. The head switch is performed from a current head to a target head. Prior to the head switch, the system determines if the current cylinder is in either the inner zone or the outer zone. When the current cylinder is in either the inner zone or the outer zone, the system seeks the current head to the middle zone, whereupon the system performs a head switch from the current head to the target head. When the current cylinder is not found to be in either the inner zone or the outer zone, i.e. when the current cylinder is in the middle zone, then the system performs the head switch from the current head to the target head without first performing a seek. After either of the above described head switch operations, the system seeks the target head to the target cylinder, when necessary.

Head switch operations in a magnetic disk system

A method and apparatus for performing head switch operations in a magnetic disk system with a magnetic disk device that is segmented into a plurality of cylinders. The cylinders are grouped into an inner zone, a middle zone, and an outer zone. The inner zone is near the innermost area of the magnetic disk device. The outer zone is near the outermost area of the magnetic disk device. The middle zone is in between the inner zone and the outer zone. The head switch is performed from a current head at a current cylinder to a target head at a target cylinder. Prior to the head switch, the system determines if the current cylinder is in either the inner zone or the outer zone. If the current cylinder is in either the inner zone or the outer zone, then the system determines if the target cylinder is in either the inner zone or the outer zone. If the target cylinder is in either the inner zone or the outer zone, then the system seeks the current head to the middle zone and then performs the head switch. If the target cylinder is in the middle zone, then the system seeks the current head to the target cylinder and then performs the head switch. If the current cylinder is in the middle zone, then the system performs the head switch without seeking. After the head switch, the system seeks the target head to the target cylinder.

A method and data structure for a header-formatted defective sector management system. A spare sector is allocated for each n sectors. When a defective one of the n sectors is identified, the sectors are slipped using the spare sector. The location of the defective sector and the type of defect, e.g., data field or header field, is indicated by a data structure written to the header field of at least one of the non-defective sectors. When a second defective sector is identified, the system operates to disposition the second defective sector based on the type of the first defective sector. If the first defective sector was a defect in the data field and the second defective sector is a defect in the header field then the first defective sector is converted to a reassigned sector and the second defective sector is slipped. This avoids the problem of reassigning a sector having a defective header field.

Header-formatted defective sector management system

A system for halting operation of a hard disk controller when a write operation occurs during a servo positioning error condition including a memory cell for retaining an indication of whether a write operation occurred during the previous servo sector. A memory cell, such as a flip flop, is set on any occurrence of a write operation. With the reading of a next servo field, the output of the first flip flop is latched to a second flip flop. During a present servo sector, a servo positioning error signal is logically AND'ed with a write gate active signal where the write gate active signal is enabled if write gate is active in the present servo sector or write gate was active in the previous servo sector (as indicated by the output from the second flip flop.

Servo error response system on a magnetic disk device

A disk resident system for managing defective data sector information in a defective data sector map in a headerless format magnetic disk device. The defective data sector map is stored in gaps between fields in the headerless disk format itself or in existing disk administration fields. The defective data sector map includes a plurality of binary digits that individually correspond to a defective or non-defective status of an individual data sector on at least one section of at least one track proximate to the defective data sector map. The defective data sector map can be minimized by compressing repetitive 0's or 1's in the map. ECC coding and/or other redundancy checks can be included to ensure validity of the defective data sector map.

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Berthoud, CO, United States of America

Aaron Wade Wilson