Compaq Computer Corporation, Inc.

Hewlett-packard Development Company, L.p.

Stephen M Schultz

Mark J Thompson

David L Flower

E David Neufeld

David S Schmenk

David L Grant

Richard A Ewert

Nhan Q Vo

Sohail Hameed

Thomas W Grieff

Mark Lyndon Oelke

Joseph David Black

Randy D Schneider

Thomas W Lattin, Jr

Jay E Allison, Jr

Chiung-Sheng Wu

Mohammad A Ramiz

Chiung-Shang Wu

Hung D Dao

Rajavel Gnanapragasam

Darren R Thomas

Scott M Pfeffer

Dan Mazina

Benjamin T Allen

A system having input/output hot spot tracking is disclosed. The storage system includes a storage device, a host controller coupled to the storage device, and a tracking engine coupled to the host controller and the storage device. The host controller is configured to managed input/output of the storage device. The tracking engine includes a storage map cycling between active status and passive status. Input/output commands are stored in the storage map during the active status. Like input/output commands in the storage map during active status are counted and compared to a number. Counts greater than the number are reported as input/output hot spots.

Input/output hot spot tracking

A storage system is disclosed including storage devices configured to store data, and a logical storage volume coupled to the storage devices and configured to store a subset of the data as segments. The storage system also includes a controller including a cache and memory. The memory is configured to include records such that each record corresponds with a segment in the logical storage volume and each record includes information regarding data stored in the corresponding segment. The controller is configured to access the records in response to a cache miss of the cache to determine if requested data from the cache miss is stored and ready for access in the logical storage volume. The controller is also configured to update the subset of data stored in the segments as a function of cache misses.

Storage system with middle-way logical volume

Storage controllers and related methods of operation are described. One method tracks storage access operations to a logical disk. The method persistently identifies storage blocks that have been accessed. Responsive to the identifying, the method selectively skips subsequent operations to storage blocks that have not been accessed.

System and method for reorganizing data in a raid storage system

A system and method for synchronizing firmware revisions in redundant controllers in a storage system is disclosed. Redundant controllers transmit firmware revision numbers during the establishment of a communication links between the controllers. The revision numbers are compared and, if they are not equal, then controller that possesses the more recent firmware revision transmits its firmware across the communication link to the other controller. The more recent firmware is stored in the memory of the other controller, which is then re-booted to ensure that both controllers are operating with the same firmware. If a failed controller is replaced or rebooted while the other controller remains operational, then the firmware revision from the operational controller is transmitted to the replaced or re-booted controller and stored in its memory. The controller is then re-booted to ensure that both controllers are operating with the same firmware.

Array controller ROM cloning in redundant controllers

A method of operating a storage controller that receives data access requests containing a logical block address and a count of blocks involved in the access request. A record is generated and persistently stored indicating whether particular logical block addresses have been accessed since creation. The persistent record is subsequently accessed to enable selected operations to be skipped or aborted when they selected operations involve logical block addresses that have never been accessed.

A new and improved apparatus and method for rebuilding a replacement disk of a fault tolerant, mass storage drive array subsystem of a computer system. The method calls for a microprocessor to check a stripe for consistency. If the stripe is inconsistent, the microprocessor rebuilds a predetermined number of stripes. If the checked stripe is consistent, then the microprocessor checks a next stripe and repeats the above-described process. Because the drive array subsystem receives both system requests and rebuild requests, the present invention allows a user to select the drive array subsystem's priority in processing system requests versus rebuild requests, thereby allowing greater system access to the drive array subsystem during peak times of system requests.

User selectable priority for disk array background operations

For use with a computer system having an intelligent mass storage disk array subsystem, including a microprocessor controller, a method for the distribution of data within the disk array based upon logical commands issued by the computer system. The disk controller reads a logical command and translates the commands into multiple drive specific commands, including drive physical parameter information such as head, sector and cylinder selection. The calculation of these physical parameters is based upon a number of factors including the operating system installed in the computer system, the type of interleave scheme, if any, specified by the computer system configuration, and disk specific parameters. The physical drive requests are then placed in a queue and executed by the microprocessor controller. The method also encompasses a method for creating a disk array configuration to be loaded on all disks within the array based on existing valid disk array information and configuration information maintained by the computer system.

Data distribution in a disk array

A method and apparatus which indicates the physical location of one or more peripheral devices. A system operator uses an input device to select an icon that is displayed on a display device. The icon represents a single peripheral device or a group of peripheral devices among a plurality of peripheral devices. For example, an icon may represent a disk drive, a group of disk drives disposed within a storage unit, an array of disk drives, an array of disk drives disposed within one or more storage units, etc. After the system operator selects the icon, an indicator light associated with each of the one or more peripheral devices represented by the icon illuminates to identify the physical location of the selected peripheral device or devices. Other peripheral devices are contemplated, such as a bank of modems, floppy drives, CD-ROM drives, etc.

System for identifying the physical location of one or more peripheral

A system for performing on-line reconfiguration of a disk array in which a source logical volume is reconfigured to a destination logical volume. Disk array configuration is invoked if a new physical drive is inserted, or a drive is removed. Reconfiguration can also be performed if the user desires to change the configuration of a particular logical volume, such as its stripe size. The disk array reconfiguration is run as a background task by firmware on a disk controller board. The reconfigure task first moves data from the source logical volume to a posting memory such as RAM memory. The reconfigure task operates one stripe at a time, with the stripe size being that of the destination logical volume. Once a stripe of data is moved into the posting memory, it is written back to corresponding locations in the destination logical volume. The reconfigure task continues until all data in the source logical volume have been moved into the destination logical volume. While the reconfigure task is working on a particular logical volume, data remains accessible to host write and read requests.

On-line disk array reconfiguration

Method for developing physical disk drive specific commands from logical

A system for monitoring performance of an intelligent array expansion system includes a controller for communicating with a host computer and associated intelligent array expansion systems, each of which has a plurality of fixed disk drives. The controller incorporates firmware to monitor a plurality of predetermined performance data, such data being thereafter stored in information storage devices. At the same time counts are maintained for selected parameters which are of interest to a systems manager. Such counts and the performance data are stored for each one of a plurality of preselected intervals, and an indication or warning is given to the systems manager when performance data, or when a selected parameter exceeds a preselected threshold.

Drive array performance monitor

A host computer including a posted write cache for a disk drive system where the posted write cache includes battery backup to protect against potential loss of data in case of a power failure, and also including means for performing a method for determining if live data is present in the posted write cache upon power-up. The posted write cache is further mirrored and parity-checked to assure data validity. Performance increase is achieved since during normal operation data is written to the much faster cache and a completion indication is returned, and the data is flushed to the slower disk drive system at a more opportune time. Batteries provide power to the posted write cache in the event of a power failure. Upon subsequent power-up, a cache signature previously written in the posted write cache indicates that live data still resides in the posted write cache. If the cache signature is not present and the batteries are not fully discharged, a normal power up condition exists. If the cache signature is not present and the batteries are fully discharged, then the user is warned of possible data loss. A configuration identification code assures a proper correspondence between the posted write cache board and the disk drive system. A mirror test executed to verify data validity. Temporary and permanent error conditions are monitored so that posted write operations are only enabled when error-free operation is assured.

Growing community of inventors

Houston, TX, United States of America

Stephen M Schultz