Energy-efficient CPU utilization based virtual machine scheduling in Green clouds

Cloud Computing is based on virtualization; it provide users pay-per-use computing resources by internet without managing infrastructure. With the increase demand of Cloud more and more attention is given to energy consumption and power saving of Cloud data centres. Energy savings can be achieved by continuous consolidation of VM´s according to current utilization and thermal state of computing nodes. Consolidation is the first step towards Green Computing. There is a relation between resource management and consolidation. Migration of virtual machines in Cloud Computing also provides us an opportunity for energy savings. We can say that migration is done on basis of workload management so that it will not exceed the power consumption or temperature of host beyond a certain limit. In migration a key challenge is to find the source and target machine. There are different reasons of migration, the main is idle power wastage and it is major cause of energy inefficiency.