Abstract: A method for sharing memories of virtual machines is provided. The method is applied for a computer system configured to execute at least one virtual machine. The method includes the following steps. A memory map corresponding to the virtual machines is obtained, wherein usage states of memory pages of the virtual machine are stored in the corresponding memory map. Unused memory pages of the virtual machines are marked as free pages according to the corresponding memory map. The free pages of the virtual machines are shared. Therefore, the unused memory pages in the virtual machine can be shared. A computer system using the foregoing method is also provided.

Abstract: In one embodiment, an apparatus for managing hypercalls in a hypervisor having an interrupt handler and a schedule is described. A deferrable low-overhead hypercall (DLH) module is configured to assign a separate DLH queue to each of a plurality of virtual machines when the virtual machine is initialized. Each entry in the separate DLH queue represents a hypercall routine. When one of the virtual machines notifies the interrupt handler of at least a deferrable hypercalls to be executed, the scheduler selects at least a virtual CPU (VCPU) and assigns them to the virtual machine to run on at least a physical CPU (PCPU). The DLH module executes the at least a deferrable hypercall inserted in a DLH queue assigned to the virtual machine before restoring the VCPU context to the virtual machine having the at least an assigned VCPU.

Abstract: A method for sharing memories of virtual machines is provided. The method is applied for a computer system configured to execute at least one virtual machine. The method includes the following steps. A memory map corresponding to the virtual machines is obtained, wherein usage states of memory pages of the virtual machine are stored in the corresponding memory map. Unused memory pages of the virtual machines are marked as free pages according to the corresponding memory map. The free pages of the virtual machines are shared. Therefore, the unused memory pages in the virtual machine can be shared. A computer system using the foregoing method is also provided.

Abstract: In one embodiment, an apparatus for managing hypercalls in a hypervisor having an interrupt handler and a schedule is described. A deferrable low-overhead hypercall (DLH) module is configured to assign a separate DLH queue to each of a plurality of virtual machines when the virtual machine is initialized. Each entry in the separate DLH queue represents a hypercall routine. When one of the virtual machines notifies the interrupt handler of at least a deferrable hypercalls to be executed, the scheduler selects at least a virtual CPU (VCPU) and assigns them to the virtual machine to run on at least a physical CPU (PCPU). The DLH module executes the at least a deferrable hypercall inserted in a DLH queue assigned to the virtual machine before restoring the VCPU context to the virtual machine having the at least an assigned VCPU.