Thread: Ensuring Less Power Consumption

There are both proactive and reactive techniques with respect to reducing power consumption in computer devices. Proactive techniques: These techniques a pri¬ori ensure that devices consume less power. For example, one can cut down on the number of disks being used by using higher capacity disks. A one-terabyte disk will consume less power than ten 100 gigabyte disks. Similarly, one canreduce the number of copies of data, use data compression, thin provisioning and data de¬duplication techniques to reduce the amount of data being stored on disks. This, in turn, reduces the number of disk drives being used which, in turn, leads to less power consumption. Similarly, one can also use Flash drives or higher efficiency power supplies to also proactively cut down on the amount of power being consumed.



Reactive techniques

In reactive techniques one dynamically changes the state of a physical resource from high power consuming state to low power con¬suming state. The state of CPU, memory and disk drives can be dynamically transitioned between dif ferent power states. It is important to note that there is a trade-off between power consumption and per¬formance when one transitions a device to a lower power state. For example, if we spin down or shut down a disk drive, the next time we want to read data from that drive we will incur higher latency. This is not acceptable behavior for all the different types of workloads. For example, interactive applica¬tions cannot wait for disks to spin up.