Clustered object state using field set operations

• US 20060271575A1
• Filed: 05/25/2006
• Published: 11/30/2006
• Est. Priority Date: 05/25/2005
• Status: Abandoned Application

• Current Assignee: Orion D. Letizi, Steven T. Harris, Timothy S. Eck
• Original Assignee: Orion D. Letizi, Steven T. Harris, Timothy S. Eck
• Inventors: Letizi, Orion D., Eck, Timothy S., Harris, Steven T.
• Application Number:
  US11/442,522
• Publication Number:
  US 20060271575A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 11/1479 Generic software techniques for error detection or fault masking
• CPC Class Codes: G06F 11/203 using migration
• CPC Class Codes: G06F 16/217 Database tuning G06F16/2282 takes precedence; database performance monitoring G06F11/3409
• CPC Class Codes: G06F 16/24552 Database cache management
• CPC Class Codes: G06F 2209/522 Manager
• CPC Class Codes: G06F 9/445 Program loading or initiating bootstrapping G06F9/4401; security arrangements for program loading or initiating G06F21/57
• CPC Class Codes: G06F 9/45504 Abstract machines for programme code execution, e.g. Java virtual machine [JVM], interpreters, emulators
• CPC Class Codes: G06F 9/52 Program synchronisation; Mutual exclusion, e.g. by means of semaphores
• CPC Class Codes: G06F 9/526 Mutual exclusion algorithms
• CPC Class Codes: G06F 9/544 Buffers; Shared memory; Pipes

Abstract

Technology for sharing data among multiple virtual machines in a cluster of virtual machines is disclosed. Each virtual machine identifies “managed” objects of an instance of an application running at the virtual machine. Operations performed by an instance of one application which affect the state of managed objects are detected and distributed. The technology distributes object state of managed objects by distributing underlying object field data. A cluster of virtual machines each detects changes to objects of an application running at the virtual machine at a field level of granularity and communicates information with other virtual machines in the cluster to replicate the changes to local instances of a managed object at other virtual machines.

Claims

1. A computer-implemented method for maintaining consistent data at different virtual machines, comprising:

defining one or more managed objects on a instance of a virtual machine in a cluster of virtual machines, each having an instance of an application;

detecting an object field change in a managed object at a first virtual machine;

distributing said field change to at least a second virtual machine in the cluster having a local instance of the managed object.

2. The computer-implemented method of claim 1 further including:

creating a central representation of managed objects at a central manager, and

replicating or object field data change at said central representation.

3. The computer implemented method of claim 2 wherein the step of distributing includes forwarding information from the central manager to replicate the field change in a local instance of the managed object on at least the second virtual machine.

4. The computer-implemented method of claim 1, further comprising:

receiving information regarding detected changes to managed objects by one or more virtual machines in the cluster.

5. The computer implemented method of claim 1 wherein the step of defining includes identifying a root managed object, and the step of detecting includes detecting new managed objects which are children of said root object.

6. A computer-implemented method for maintaining consistent data at clustered virtual machines, comprising:

maintaining a central representation of one or more managed objects instantiated ate one or more of the clustered virtual machines;

receiving information including at least a field data change in a managed object from a first virtual machine; and

sharing the information with at least a second virtual machine to replicate the changes to the local instance of the one or more managed objects at the second virtual machine.

7. The computer-implemented method of claim 6, wherein:

the received information includes an operation on the field level data affected by an invoked method.

8. The computer-implemented method of claim 6 further including:

replicating said field data change in said central representation.

9. The computer-implemented method of claim 6, wherein the step of sharing comprises:

sending a transaction identifying the field data change to said at least second virtual machine.

10. The computer implemented method of claim 9, further including the steps of defining a set of managed objects, including identifying a root managed object, and the step of receiving includes receiving information identifying newly created managed objects which are children of said root object.

11. A computer-implemented method for maintaining consistent data at clustered virtual machines, each virtual machine having an instance of an application, comprising:

receiving at a first virtual machine information comprising at least a field change to a local instance of a managed object, the information resulting from a change to a local instance of the managed object at a second virtual machine; and

replicating the changes in the local instance of the managed objects at the first virtual machine.

12. The computer implemented method of claim 11 wherein the step of receiving includes receiving from a central manager.

13. The computer-implemented method of claim 12, wherein:

the central manager includes a central representation of the managed objects and uses the information to replicate the changes at the field level of granularity at the central representation of the objects.

14. The computer-implemented method of claim 11, wherein:

the information identifies an operation on the field data affected.

15. The computer-implemented method of claim 11, wherein:

only changes to objects which are identified as managed objects at the second virtual machine are detected.

16. The computer-implemented method of claim 11, further comprising:

instrumenting byte code of the first instance of the application to perform the receiving and using.

17. The computer implemented method of claim 11, wherein the step of receiving includes receiving information identifying newly created managed objects which are children of a root object.

18. The computer implemented method of claim 14 wherein the central representation is a meta-data representation of each managed object in the cluster.