| 摘要 |
A technique is described for managing processor (CPU) resources in a host having virtual machines (VMs) executed thereon. A target size of a VM is determined based on its demand and CPU entitlement. If the VM's current size exceeds the target size, the technique dynamically changes the size of a VM in the host by increasing or decreasing the number of virtual CPUs available to the VM. To “deactivate” virtual CPUs, a high-priority balloon thread is launched and pinned to one of the virtual CPUs targeted for deactivation, and the underlying hypervisor deschedules execution of the virtual CPU accordingly. To “activate” virtual CPUs, the number of virtual CPUs, the launched balloon thread may be killed. |
| 主权项 |
1. A method for managing CPUs in a host having a virtual machine executing thereon, wherein the virtual machine is allocated a plurality of virtual CPUs, the method comprising:
determining a target number of virtual CPUs for a virtual machine based on processor demand by the virtual machine and that is in excess of a current number of virtual CPUs activated for the virtual machine; launching a prioritized process thread in a guest operating system of the virtual machine, wherein the prioritized process thread is associated with a first virtual CPU of the plurality of virtual CPUs and includes a halt instruction; executing, by operation of a guest scheduler in the guest operating system, the prioritized process thread using the first virtual CPU of the plurality of virtual CPUs; and responsive to detecting, by operation of a hypervisor in the host, that the first virtual CPU is executing the halt instruction, descheduling execution of the first virtual CPU on one or more physical CPUs of the host. |
