Techniques for managing virtual machine (VM) states
View Patent ↗Techniques for managing virtual machine (VM) states are provided. Applications executing within a processing context of a VM communicate outside that processing context with a hypervisor or VM Monitor (VMM) to have the hypervisor perform host operations for the VM.
1. A processor-implemented method residing in a machine-readable storage medium and to execute on a processor, the method, comprising:
receiving, by the processor, a request to save a state of a Virtual Machine (VM), the request received within a processing context of the VM and the request sent from a helper process processing on the VM and the helper process does not wait for response to sending the request, the request sent asynchronously and processed asynchronously by the processor;
passing, by the processor, the request to a hypervisor that executes on the processor outside the processing context of the VM;
detecting, by the processor, an event raised by the hypervisor indicating the state was saved for the VM; and
notifying, by the processor, one or more VM applications executing within the processing context of the VM that the state was saved for the VM.
2. The method of claim 1 , wherein receiving further includes receiving the request from a particular one of the one or more VM applications within the processing context of the VM, the particular one of the one or more VM applications is the helper process.
3. The method of claim 1 , wherein passing further includes writing the request to a predefined memory region allocated to the VM that the hypervisor monitors.
4. The method of claim 1 , wherein passing further includes one of:
writing the request to a predefined port of the processor that the hypervisor listens on for communication coming from within the processing context of the VM; and
writing the request to a virtual Input/Output (I/O) port of the VM that is accessible to the hypervisor outside the processing context of the VM.
5. The method of claim 1 , wherein passing further includes including credentials with the request passed to the hypervisor that the hypervisor uses to authenticate the request to save the state of the VM.
6. The method of claim 1 , wherein passing further includes asynchronously passing the request to the hypervisor and returning control back to the VM while the hypervisor processes the request.
7. The method of claim 1 , wherein detecting further includes dynamically listening for the event on one of the following: a virtual port of the VM that is accessible to the hypervisor, a predefined port that the hypervisor writes the event to; and a predefined memory region of the VM that the hypervisor has access to write the event to.
8. A machine-implemented system, comprising:
a Virtual Machine (VM) application implemented in a computer-readable storage medium and to execute on one or more processors within an internal processing context of a VM; and
a VM helper process implemented in a computer-readable storage medium and to execute on the one or more processors within the internal processing context of the VM;
wherein the VM application is configured to asynchronously issue a request to save a VM state to the VM helper process, the VM helper process is configured to asynchronously communicate outside the internal processing context of the VM with a VM Monitor (VMM) to have the VMM asynchronously save the state of the VM on behalf of the VM application.
9. The system of claim 8 , wherein the VM application registers with the VM helper process to receive notifications from the VMM for the VM.
10. The system of claim 8 , wherein the VM helper process is to communicate with the VMM via one or more of the following: a reserved portion of memory or storage reserved for the VM, a virtual Input/Output (I/O) port that the VMM has access to, and a predefined designated port that the VMM monitors.
11. The system of claim 8 , wherein the VM application is configured to pass credentials to the VM helper process that the VM helper process communicates to the VMM and that the VMM uses to authenticate the VM application before saving the state on behalf of the VM application of the VM.
12. The system of claim 8 , wherein the VM helper process is configured to asynchronously communicate with the VMM.
13. The system of claim 8 , wherein the VM helper process is configured to notify the VM application when the VM helper process receives notice that the VMM has saved the state of the VM on behalf of the VM application.
14. A machine-implemented system, comprising
a Virtual Machine (VM) implemented in a computer-readable storage medium and to execute on one or more processors; and
a hypervisor implemented in a computer-readable storage medium and to execute on the one or more processors;
wherein the hypervisor is configured to expose selective portions of its Application Programming Interface (API) to a VM helper process that executes inside a processing context of the VM, the hypervisor further configured to asynchronously perform one or more operations from the API on behalf of the VM helper process and asynchronously communicate results of performing those operations to the VM helper process.
15. The system of claim 14 , wherein the hypervisor is configured to restore the VM to a previously saved state when processing a select one of the operations on behalf of the VM helper process.
16. The system of claim 14 , wherein the hypervisor is configured to reconfigure the VM in response to parameters received from the VM helper process when processing a select one of the operations on behalf of the VM helper process.
17. The system of claim 14 , wherein the hypervisor is configured to process parameter data when processing a select one of the operations on behalf of the VM helper process and communicate back to the VM helper process another set of data obtained from processing the select operation.
18. The system of claim 14 , wherein the hypervisor is configured to receive communication from the VM helper process via a first predefined port within the VM and the hypervisor is configured to communicate the results back to the VM helper process via a second predefined port within the VM.