Thread: Increasing resource utilisation Memory and CPU,

Increasing resource utilisation Memory, CPU, fan, network cards and disks are some important computer resources that consume power. The input workload deter¬mines how much work these resources have to perform, and this, in turn, dictates the amount of power consumed by the computer system. It is interesting to note that the amount of power consumed by a system that is 50 per cent utili sed is not that much more than a computer system that is 10 per cent utilised (due to the presence of fixed power consumption costs). Hence, less power is consumed by a single box that is 50 per cent utilised than five boxes that are each only 10 per cent utilised.

In the past, the software running on a box was very tightly coupled to the hardware box, and thus, it was very difficult to dynamically move an application from one computer to another. However, with the emergence ofhypervisor (server virtualisation) technologies like Xen, HyperV, and VMWare, now it is possible to dynamically move applications between computer systems, and thus, increase the overall system utilisation.



The hypervi¬sor technology allows multiple applications to run on a single box, and the failure of a single appli¬cation does not affect tlle execution of the other applications running on the computer. The hyper¬visor technology has been around since 1960s (illM VM operating system), but only now this technol¬ogy has been made available to run on commodity hardware systems, and thus, it has become more prevalent. Most datacentre operators are re-design¬ing their datacentres to leverage this technology.