International Business Machines Corporation

Will A Wright

Lokesh M Gupta

Matthew G Borlick

Michael T Benhase

John Charles Elliott

Christopher J Strauss

Kevin J Ash

Alex Chliwnyj

Eric Alan Eckberg

Brian James Cagno

Scott Alan Shurson

Dale Huber Anderson

Angel E Delgado

Markus Navarro

Pamela Ruth Nylander-Hill

Scott Milton Fry

Dale A Christiansen

David C Graves

Loyal Keith Whitted

James C Simkins

Habib M Torab

John Raymond Haider

Michael A Brewer

James W Wolf

Provided are a computer program product, system, and method for recovering storage devices in a storage array having errors. A determination is made to replace a first storage device in a storage array with a second storage device. The storage array is rebuilt by including the second storage device in the storage array and removing the first storage device from the storage array resulting in a rebuilt storage array. The first storage device is recovered from errors that resulted in the determination to replace. Data is copied from the second storage device included in the rebuilt storage array to the first storage device. The recovered first storage device is swapped into the storage array to replace the second storage device in response to copying the data from the second storage device to the first storage device.

Recovering storage devices in a storage array having errors

Provided are a computer program product, system, and method for adjusting active cache size based on cache usage. An active cache in at least one memory device caches tracks in a storage during computer system operations. An inactive cache in the at least one memory device is not available to cache tracks in the storage during the computer system operations. During caching operations in the active cache, information is gathered on cache hits to the active cache and cache hits that would occur if the inactive cache was available to cache data during the computer system operations. The gathered information is used to determine whether to configure a portion of the inactive cache as part of the active cache for use during the computer system operations.

Adjusting active cache size based on cache usage

In one general embodiment, a server rack is provided. The server rack includes a sidewall having at least one fixed rail, and an aperture in the sidewall. Further, the server rack includes a retractable terminal configured to extend through the aperture of the sidewall on sliding rails configured to slide along the at least one fixed rail in a direction parallel to the sidewall. In another general embodiment, a server rack is provided. The server rack includes a sidewall and an aperture in the sidewall. The server rack also includes a first fixed rail within the sidewall, a second fixed rail within the sidewall, a retractable terminal configured to extend through the aperture of the sidewall on sliding rails configured to slide along the first and second fixed rails, and an immovable cable bracket mounted on one of the fixed rails for holding a cable extending from the retractable terminal.

Zero-U rack keyboard and monitor

In one general embodiment, a server rack is provided. The server rack includes a sidewall and an aperture in the sidewall. The server rack also includes a first fixed rail within the sidewall, and a second fixed rail within the sidewall. Moreover, the server rack includes a retractable terminal configured to extend through the aperture of the sidewall.

A storage controller that includes a cache receives a command from a host, wherein a set of criteria corresponding to read and write response times for executing the command have to be satisfied. The storage controller determines ranks of a first type and ranks of a second type corresponding to a plurality of volumes coupled to the storage controller, wherein the command is to be executed with respect to the ranks of the first type. Destage rate corresponding to the ranks of the first type are adjusted to be less than a default destage rate corresponding to the ranks of the second type, wherein the set of criteria corresponding to the read and write response times for executing the command are satisfied.

Adjustment of destage rate based on read and write response time requirements

A storage controller that includes a cache, receives a command from a host, wherein a set of criteria corresponding to read response times for executing the command have to be satisfied. A destage application that destages tracks based at least on recency of usage and spatial location of the tracks is executed, wherein a spatial ordering of the tracks is maintained in a data structure, and the destage application traverses the spatial ordering of the tracks. Tracks are destaged from at least inside or outside diameters of disks at periodic intervals, while traversing the spatial ordering of the tracks, wherein the set of criteria corresponding to the read response times for executing the command are satisfied.

Periodic destages from inside and outside diameters of disks to improve read response time via traversal of a spatial ordering of tracks

Periodic destages from inside and outside diameters of disks to improve read response times

The present invention provides a cleaning apparatus for cleaning the air bearing surface of a magnetic head of a tape drive by employing components of an actuator for oscillating the magnetic head against bristles of a brush assembly. Circuitry is provided which senses the appropriate time to commence the cleaning action and continues the cleaning action for an appropriate duration when the magnetic tape is off the magnetic head. The circuitry causes the actuator to move the magnetic head in oscillatory motion against stationary bristles of a brush assembly which are selectively brought into engagement with the magnetic head. The engagement and disengagement of the bristles with respect to the magnetic head are implemented by a lever arm which has camming surfaces which are engageable with a leader pin which moves a leader block and magnetic tape about a guide and across the magnetic head.

Oscillating magnetic head and stationary brush cleaning apparatus

A data storage system includes a data storage medium, such as a magnetic tape, that has a first control data storing area or drive partition that is addressable only by a peripheral drive mounting the medium and a plurality of other addressable data storing partitions for storing data. A volume table of contents may be stored in one of the addressable partitions. A tachometer measures and indicates physical locations on the storage medium. Each of the partitions have an extent on the storage medium indicated by said physical locations. The control data in the drive partition includes directories of medium control blocks, such as tape marks, defect marks and the like; directory of all addressable partitions including the physical locations at the beginning of each partitions and other medium physical and logical parameter data. A so-called mount-demount medium control block in the drive partition indicates a demount status that shows all data stored in the drive partition is valid. Loading a storage medium into a drive does not mount the drive for recording and reading. First, a copy of the drive partition stored data is copied to a memory in the peripheral drive and the mount-demount medium control block is marked to indicate the storage medium is mounted. Then, the peripheral drive can indicate to an attaching unit that the storage medium is mounted for use in data processing activities.

Control of record media using device only accessible control areas and

A magnetic tape drive simultaneously senses on a magnetic tape three evenly spaced-apart servo track areas for servoing a multi-track magnetic head to follow a concurrent set of data tracks on the magnetic tape. The data tracks are arranged into a plurality of track groups. Each track group has a first and second subgroup of data tracks. The first subgroup of tracks are scanned in a first relative motion of the magnetic tape and magnetic head as a forward direction (tape is being spooled from a supply tape reel). The second subgroup of tracks are scanned in a second relative motion of the magnetic tape and magnetic head that is opposite in direction to the first relative direction and is a forward direction of scanning. While writing data in any one of the plural track groups, a servo dropout affecting most of the servo track areas is detected and indicated as a servo error. Writing is aborted. The relative position of the magnetic tape and head is detected at both longitudinal ends of the servo dropout. A servo dropout block (SDB), a tape control block, is written at each longitudinal end of the servo dropout only in the group of tracks in which data are being written. The tape space between the two SDBs is termed a limited portion of the tape in which no recording is permitted.

Growing community of inventors

Tucson, AZ, United States of America

Will A Wright