Patent ID: 7340617

Claim:
For use in a data storage system, a method of dynamically controlling storage device power supply current, the method comprising: monitoring at least one parameter related to power usage of the data storage system wherein the at least one parameter related to power usage comprises total current consumed by the data storage system; receiving an IO request when the data storage system is at an idle state; determining when power usage by the data storage system is greater than a first predetermined level; returning to the idle state when the power usage by the data storage system is greater than the first predetermined level; determining when the power usage by the data storage system is greater than a second predetermined level when the power usage by the data storage system is equal to or less than the first predetermined level; setting a delay factor when the delay is not set, and determining whether an inter-IO delay has expired when the power usage by the data storage system 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 power usage by the data storage system is equal to or less than the second predetermined level.