Storage Technology Corporation

Mark C Briel

Barry Lynn Bradford

Stephen S Selkirk

William A Burns

Paul Allen Wewel

Nicholas J Krull

P Frank Wynhamer

Barry L Bradford

For use in a data storage system, a method of dynamically controlling accesses to and from the storage device array. The method includes monitoring the type and frequency of IO requests to the devices to determine the duty cycle and monitoring at least one parameter related to power usage, receiving or having at least one IO request pending when the data storage system completes the IO and returns to the Idle state, determining when the power usage by the array is greater than the first predetermined level, returning to the idle state when the power usage of the array is greater than the first predetermined level, determining when the duty cycle or the power usage by the array is greater than the second predetermined level when the power usage by the array is equal to or less than the first predetermined level, presenting and alert signal, setting a delay factor when the delay is not set, and determining whether an inter-IO delay has expired when the duty cycle or power usage by the array is greater than the second predetermined level, returning to the idle state when the inter-IO delay has not expired, and performing a respective IO operation in response to the Io request and returning to the idle state when the inter-IO delay has expired, and when the duty cycle or the power usage by the array is equal to or less than the second predetermined level.

System and method of dynamically controlling storage device access duty cycle

An apparatus and method for workload balancing along multiple communication paths to a plurality of devices. The apparatus includes a controller that accumulates path usage information and a path balancing device that makes use of the accumulated path usage information to perform a path balancing operation. The path balancing method involves the path balancing device calculating the total expected connect time for all I/O messages issued to each of a plurality of peripheral devices during a predefined sampling period. These totals are then added for each communication path for the sampling period to obtain path totals. The path totals are then compared to see if a difference between the highest used path and the lowest used path is greater than a threshold amount. If the difference is higher than the threshold amount, the peripheral device having a total expected connect time that is closest to a target value is moved from the highest used path to the lowest used path.

Method, apparatus and computer program product for workload balancing among multiple communication of paths to a plurality of devices

Method and apparatus for workload balancing along multiple communication paths to a plurality of devices

A direct access storage device (DASD) controller system for serves computer elements such as processors and disk arrays through a serial interconnect scheme. The system includes a plurality of adapters belonging to either a first set or a second set. Cache memory is divided into master memory cards and slave memory cards, each slave memory card in communication with a corresponding master memory card. A plurality of bidirectional multichannel serial data links connects one adapter with one memory card such that every adapter in the first set of adapters is connected to every master memory card and such that every adapter in the second set of adapters is connected to every slave memory card.

High bandwidth cache system

A multi-port switching system and method for a computer bus allows for selective coupling of a number of bus initiator devices to at least one bus target device to simulate a dual-ported interface to the bus target device. By use of a number of switching circuits corresponding with the bus initiator busses, a single-ported bus target device may be utilized in applications where dual-ported or greater interfaces are required. The multi-port switching system and method utilizes a low-cost hardware based design which adds minimal overhead to the operation of the computer bus.

Growing community of inventors

Louisville, CO, United States of America

Mark C Briel