Method for updating operating system without memory reset

• US 9,063,821 B1
• Filed: 07/22/2014
• Issued: 06/23/2015
• Est. Priority Date: 12/31/2011
• Status: Active Grant

• Current Assignee: Virtuozzo International GmbH
• Original Assignee: Parallels Holdings Limited (HNA Technology Co. Ltd.)
• Inventors: Emelyanov, Pavel, Tormasov, Alexander G.
• Primary Examiner(s): Khatri, Anil
• Application Number:
  US14/337,384
• Time in Patent Office: 336 Days
• Field of Search: 717168-174, 709/203
• US Class Current: 1/1
• CPC Class Codes: G06F 2009/45562 Creating, deleting, cloning virtual machine instances
• CPC Class Codes: G06F 8/656 while running
• CPC Class Codes: G06F 9/4406 Loading of operating system
• CPC Class Codes: G06F 9/45558 Hypervisor-specific management and integration aspects

Abstract

A computer system has an OS running on it. The computer system has Virtual Execution Environments (VEEs—containers or Virtual Machines), an old OS (to be replaced), a memory area which has data needed for system restart and restore from the VEE. The VEEs are moved into snapshot and a new OS is loaded into the memory. The new OS launches and receives data needed for restore of the system from the snapshot. Then, the new OS activates the VEEs. Thus, the new OS is reloaded onto the computer system without a physical memory reset.

Claims

1. A computer-implemented method for updating an operating system (OS) without a memory reset, the method comprising:

launching a Virtual Execution Environment (VEE) under a host OS of a computer system;

generating a snapshot of the VEE, including snapshotting user process data that is located in a random access memory, of any processes that run under the VEE;

loading a new OS onto the computer system;

giving control to the new OS;

ensuring that the user process data that is part of the snapshot of the VEE is unaffected by the loading of the new OS and that the user process data remains in its original location;

re-launching the VEE under the new OS; and

using a designated component to restore the user process data from the snapshot into the memory.

2. The method of claim 1, wherein the designated component is a kernel space component and uses OS object model to generate the snapshot.

3. The method of claim 1, wherein the designated component is a user space component and uses OS API to generate the snapshot.

4. The method of claim 1, wherein the VEEs are containers.

5. The method of claim 1, wherein the VEEs are Virtual Machines (VMs).

6. The method of claim 1, further comprising transferring VEE files to a file system cache and restoring the files from the file system cache upon transferring control to the new OS.

7. The method of claim 1, further comprising:

creating a temporary file system filled with blank blocks;

transferring a kernel state into the temporary file system; and

restoring the kernel state upon transferring control to the new OS.

8. The method of claim 1, further comprising using VEE checkpoints.

9. The method of claim 1, wherein the ensuring is performed using digital signatures.

10. The method of claim 1, wherein the ensuring is performed using checksums.

11. The method of claim 1, wherein the VEE snapshots are compressed.

12. A system for updating an operating system without a memory reset, the system comprising:

a processor;

a memory coupled to the processor;

a computer program logic stored in the memory and executed on the processor, the computer program logic for implementing the steps of;

launching a Virtual Execution Environment (VEE) under a host OS of a computer system;

generating a snapshot of the VEE, including snapshotting user process data that is located in a random access memory, of any processes that run under the VEE;

loading a new OS onto the computer system;

giving control to the new OS;

ensuring that the user process data that is part of the snapshot of the VEE is unaffected by the loading of the new OS and that the user process data remains in its original location;

re-launching the VEE under the new OS; and

using a designated component to restore the user process data from the snapshot into the memory.

13. A non-transitory computer-useable storage medium storing computer code for implementing the steps of:

launching a Virtual Execution Environment (VEE) under a host OS of a computer system;

generating a snapshot of the VEE, including snapshotting user process data that is located in a random access memory, of any processes that run under the VEE;

loading a new OS onto the computer system;

giving control to the new OS;

ensuring that the user process data that is part of the snapshot of the VEE is unaffected by the loading of the new OS and that the user process data remains in its original location;

re-launching the VEE under the new OS; and

using a designated component to restore the user process data from the snapshot into the memory.