Patent ID: 7870122
Filing Date: 2011-01-11
Classification: G06F

Abstract:
1. A method, comprising: receiving a request for a read or write operation on a node of a data structure, the data structure includes a plurality of nodes, and wherein the method further comprises, prior to receiving a request, setting the mode of the plurality of nodes to a same mode and setting a working variable to zero; determining a current mode of the node; adding, to the working variable, a difference between a first cost of performing the operation in the current mode and a second cost of performing the operation in an alternate mode; determining whether the working variable is at least equal to a sum of a third cost of translating the node from the current mode to the alternate mode and a fourth cost of translating the node from the alternate mode to the current mode, wherein the first cost is based on time and energy spent in performing the operation in the current mode, the second cost is based on time and energy spent in performing the operation in the alternate mode, the third cost is based on energy consumed and time spent to translate the node from a disk mode to a log mode, and wherein the fourth cost is based on energy consumed and time spent to translate the node from the log mode to the disk mode, one or more of the first cost, the second cost, the third cost and the fourth cost being dynamically determined based on a measurement of an actual energy consumed and an actual time spent to carry out the request for a read or write operation; if the determination is affirmative, then switching the node from the current mode to the alternate mode and resetting the working variable to zero; and performing the operation on the node.