KVM allows the resources to be shared to the guest operating systems. KVM allocates the memory dynamically between many processes. KVM allows the host to allocate the memory for the guest and beyond it guest can't use memory. The guest system that has a balloon driver keeps the guest from taking full memory. This ballooning is controlled by balloon monitor. KVM allows the pages that are similar to be grouped or collapse together in one to save the space this way the dynamic memory management can be performed by KVM.
