Ronald E Walker

US Patent:

7340617, Mar 4, 2008

Filed:

Jun 1, 2004

Appl. No.:

10/858239

Inventors:

Paul A. Wewel - Broomfield CO, US
Lance J. Collins - Superior CO, US
Ronald Rae Walker - Louisville CO, US

Assignee:

Storage Technology Corporation - Louisville CO

International Classification:

G06F 1/00

US Classification:

713300, 713323

Abstract:

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.